Talk:Aldol reaction/Archive 1

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Archive This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.

Contents

Quality of Article

This article is terrible. It needs a lot of work. The aldol reaction isn't very useful?!? Eugene Kwan 07:27, 15 December 2005 (UTC)

I agree that this article is terrible and needs tons of work. I'll help out fixing it. ~K 15:47, 15 December 2005 (UTC)
  • to state that the article is terrible is not a nice gesture the 15 or so editors who have contributed thus far. the article does need serious work: improve link density, most recent additions do not have any links at all, improve pics, contribute references. V8rik 16:50, 15 December 2005 (UTC)

Fair enough, I should have used more diplomatic language. But this article is not up to the good standards Wikipedia deserves yet. I'll be adding some completely new schemes soon. --Eugene Kwan

Crossed aldol section

I caught some errors in section entitled Crossed aldol reaction. I've reworked it and entitled the section Enolate formation. Please double check my work. ~K 04:41, 16 December 2005 (UTC)

You should check out http://www.courses.fas.harvard.edu/~chem206/Fall_2005/Lectures_and_Handouts/ There's a lot of information available there. I have a few points: - you only get crossed products if there's more than one set of enolizable protons - perhaps a less colloquial word than "preformed" might be appropriate? - strictly speaking, you also need the retroaldol reaction to be slow for it to be under kinetic control. but I think that you're basically correct. - there are other ways to form magnesium enolates. wouldn't using a grignard run the risk of adding to the carbonyl? common conditions use MgBr2 OEt2 with some amine base. - it's probably worth mentioning E vs Z enolates and the effect of HMPA - good work! Eugene Kwan 06:27, 16 December 2005 (UTC)

Thanks for the tips, and good point about the MeMgBr. I remember it being more basic than nucleophilic, but I think I should remove that statement just to be sure. And, of course, there is tons more to write. You're clearly the expert on this subject. Why don't you write a little? ~K 07:36, 16 December 2005 (UTC)

I'm still working on this page...only about half done here. Please feel free to chime in... I'd appreciate any comments. Eugene Kwan 09:01, 17 December 2005 (UTC)

  • Hi Eugene, you are doing a great job, I have made a new edit: re-introduced the original introduction by user ~K, I think all articles should have such type of intro. Provided links as well. Modified the references, the part on Stereoselectivity still has too much jargon, many reactions in the See also section are captured in the aldol condensation. V8rik 16:54, 17 December 2005 (UTC)

Original references

Can someone please find the original 1872 references from Wurtz and Borodin? I can't seem to find them. ~K 18:18, 17 December 2005 (UTC)

I found the Wurtz reference. Still looking for the Borodin reference. ~K 23:48, 17 December 2005 (UTC)

Work in Progress

I've left in some empty sections to organize myself...I plan to work on this again soon. I hope this isn't against the rules... Anyone think we can get this page into the Featured Articles? That'd be so cool. Of course, it needs a ton of work before it's ready for that. Eugene Kwan 00:02, 18 December 2005 (UTC)

I was also thinking that this would be a good first chemical reaction featured article. It's a long road to a FA, but if we stick with it we can do it. When we are finished with the page, we'll submit it for peer review, and after that we'll submit it for FA status. ~K 00:28, 18 December 2005 (UTC)
Just to piggyback on here, where there's a decent chance of finding a chemist (!) we have an iodine clock reaction and Old Nassau reaction article but no general article on clock reactions. I'm hoping someone here might be inspired, once you're done with this article, of course! - Nunh-huh 00:31, 18 December 2005 (UTC)
Make this request to the Wikiproject Chemistry. I'm sure someone there can help you with this. ~K 00:45, 18 December 2005 (UTC)
Wow! I didn't know we had one! Thanks. - Nunh-huh 02:21, 18 December 2005 (UTC)

Comments

I've added lots in the stereoselectivity section...any comments? Maybe someone can do the thermo vs. kinetic enolate bit in the previous section. Eugene Kwan 03:29, 19 December 2005 (UTC)

Nature errors to correct

Peer review This article was externally reviewed (December 14, 2005) by Nature. It was found to have 3 errors.

Nature disputes the accuracy of this article; see http://www.nature.com/news/2005/051212/multimedia/438900a_m1.html and Wikipedia:External_peer_review#Nature. We're hoping they will provide a list of the alleged errors soon. —Steven G. Johnson 01:46, 15 December 2005 (UTC)

So will someone be checking this article again, or can we take down the externally reviewed tag? I urge people to check the article thoroughly for errors. Eugene Kwan 03:30, 19 December 2005 (UTC)

Nature will shortly be releasing a list of errors (or something equivalent). I think that the idea is we'll wait till then, make sure we've addressed any valid points, and then take the tag down. - Nunh-huh 03:54, 20 December 2005 (UTC)

The results of what exactly Nature suggested should be corrected is out... -- user:zanimum

  • The mechanisms of base and acid catalysed aldol reactions should have every step as an equilibrium process
  • The acid catalysed process should include the dehydration step, which occurs spontaneously under acid conditions and, being effectively irreversible, pulls the equilibrium through to product.
  • The statement that LDA is avoided at all possible as it is difficult to handle is rubbish. Organic chemists routinely use this reagent – which they either make as required or use commercially available material.
    • See link details, assuming this is the version that Nature examined: version point 1: granted, all steps should have been equilibria. point 2: not granted, condensations are covered in aldol condensation and it is clearly stated that acid conditions will lead to dehydration. point 3 not granted: Wiki states that use of LDA is cumbersome because of low temperature required 200 K not every lab has access to liquid nitrogen or dry ice. Not the use of LDA itself is questioned. V8rik 20:04, 22 December 2005 (UTC)

I agree with all three criticisms. If they haven't already been corrected, they will be corrected this weekend. ~K 01:16, 23 December 2005 (UTC)

I believe the errors found by Nature have been corrected. Could someone please verify this? ~K 03:28, 23 December 2005 (UTC)

Hi guys...here's my take:

1. I believe the equilibria problem is mostly fixed. I take the opinion that if you form an enolate using a stoichiometric amount of strong base, then that's irreversible. With soft enolization conditions, you may or may not be forming the enolate quantitatively. With boron enolates, I think you form the enolate completely. As with hydrolysis of the metal alkoxide, I think that's reasonably irreversible. So only step 3 in scheme 1 should have an equilibrium arrow. As for the enol/enolate modes scheme I drew, I guess I should have drawn an equilibrium arrow for the bottom right arrow showing addition of the enolate to the aldehyde. I can fix that later. And acid-dehydration is irreversible. I think this whole point is kind of a minor point anyways...I hardly think it's a big deal.

2. The acid-catalyzed (enol mode) mechanism indeed shows irreversible dehydration now.

3. LDA: In our group, we make our own LDA all the time. I personally find it irritating, as it might add an hour to my setup time, but I wouldn't call it "cumbersome". Heck, I wouldn't even call having to put on a chiral auxillary all that cumbersome, and that adds at least one "loading" step and one cleavage step. I'd say that the use of LDA is extremely common. At any rate, I removed the offending remark, which I guess I didn't really agree with, a long time ago.

Btw, liquid nitrogen is probably cheaper than milk most places. And dry ice is really cheap too...I mean, if they throw it on stage during various performances then it isn't too valuable. When I was in high school, I bought a huge sack of it for twenty bucks. I think that means both fall under "easily accessible".

In my opinion, the bother in making LDA (or LiHMDS) isn't really adding the BuLi to the amine, but really the annoyance of having to titrate the BuLi frequently. That means you have to dry another set of glassware, have various dry reagents, syringes, etc. etc. As the LDA article points out, you don't even need -78C to make LDA. I've certainly made it at say, -20C. The trouble is the enolate might not be stable above -78C or the aldol might not work properly.

I'll be adding more stuff soon...just busy with Christmas now. There's a lot of new material...I'd appreciate it if people would go through and check it all, since there's a lot of places where I could have messed up. I think the article no longer deserves the "errors" tag though. Merry Christmas, everyone. Eugene Kwan 22:19, 23 December 2005 (UTC)

Agree with Eugene above. LDA is not really that hard to handle and liquid N2 is dirty cheap. I think the article looks quite impresive now. After those empty sections are filled I think it would easily pass FAC. -- Rune Welsh | ταλκ | Esperanza 13:44, 25 December 2005 (UTC)
I completely agree with the Nature reviewer on all counts. Under the traditional aldol conditions of NaOR in ROH as base all steps are reversible (the dehydration step is much less so). Our page should show that, this type of method is still widely used. Indeed the standard lab prep of dibenzalacetone from acetone and benzaldehyde (see Williamson's lab text) is done in water with NaOH as catalyst – clearly the enolate is formed reversibly. I agree that low temperature LDA work is "avoided" is wrong; I was involved in making a 400 L batch of LDA in 1983 (we made an enolate at well above -78 C), and my old company (after 1987) had a plant capable of running -78 C reactions routinely on 400 L scale and larger. Dry ice is routinely used in many chemistry labs. Walkerma 20:57, 28 December 2005 (UTC)
I agree with the above statement about the traditional base-catalyzed aldol conditions: all the intermediates and products are in equilibrium. However, when using "kinetic conditions" with preformed enolates there is no (or very little) equilibrium. We should mention this. (P.S. The thought of working with 400L of LDA scares me. :) ) ~K 02:52, 29 December 2005 (UTC)

Stereochemical Models

Would someone mind checking over the stereochemical models I've put in...you know, for absolute stereochemistry, consistency, and general sense? I think it's all correct, but with so many stereocenters... I'm debating how to do the rest of the article...any sections that should be added/deleted/expanded? Eugene Kwan 22:16, 25 December 2005 (UTC)

What remains is basically a section on kinetic vs thermodynamic enolates, the Evans methodology, and an example or two from total synthesis. Also, it'd be good if we updated the links, references, and had people proofread it... I've updated the control section and restructured some of the article. Eugene Kwan 08:17, 28 December 2005 (UTC)

Eugene, your doing a great job. Keep on going! When you're done, alot of people will probably rewrite alot of what you've written, but you shouldn't take that the wrong way. We're all chipping in to make the article better. Right now, you're our "resident expert", and you've given the article much needed direction and content. I look forward to what comes next. ~K 02:41, 29 December 2005 (UTC)
Let me second that. When this is done it will be better than Britannica by far! I won't review the stereochemistry till I get home and can check things in March etc. Walkerma 03:08, 29 December 2005 (UTC)

The "new look" article - lacking basic material?

I think a lot of fantastic material has been added to this article, thanks to all who worked on that. If I had been the Nature reviewer, I would have also asked why the asymmetric aldol is not covered, and possibly the Mukaiyama aldol too, and now we have a good section on the asymmetric aldol at least. However I do have one serious criticism; the article now reads like a section from "Carey and Sundberg," i.e., it is much too advanced for the average reader. I know that my undergrads, even chem majors, would have a hard time following this article. I firmly believe that the article should provide both the basics for beginners and some more advanced and topical info for grad students and the like. I think a lot could be done with simple reorganisation; for example the base-catalysed mechanism is inextricably merged in with the diastereoselectivity, these should be separated. Does anyone mind if I do a rewrite once Eugene is finished? Walkerma 21:11, 28 December 2005 (UTC)

I agree with the criticism that there is not enough for the average reader. However, I strongly believe that Wikipedia needs to incorporate advanced content such as this to really become a world-class encyclopedia. My suggestion is that we should ADD content that would satisfy the average reader, but not remove content that would satisfy the advanced reader. ~K 02:37, 29 December 2005 (UTC)

Absolutely! I wan't being polite when I used the word fantastic! We should add to this, not take away. Walkerma 03:06, 29 December 2005 (UTC)

After re-reading this article after the recent edits I realized why I hate Org Chem so much... Maybe we could move the more technically complex sections to their own subarticles? -- Rune Welsh | ταλκ | Esperanza 03:09, 29 December 2005 (UTC)
My initial reaction to the thought of subarticles is one of horror. However, I'm willing to be convinced it may work. ~K 03:27, 29 December 2005 (UTC)

I think we can structure the article in such a way that the beginner mainly sees what they want, but the more advanced reader will look at the TOC and click to the appropriate (more advanced) piece. I would like to have a go at this after New Year if people are OK with that, perhaps we can see if it is necessary after that? It is certainly possible that large subtopics like the Mukaiyama might have their own page in time, but I think it'd be a shame to split up the core sections. Walkerma 04:17, 29 December 2005 (UTC)

Hi everyone, and thank you for the input. I'd like to address some of your comments, and tender some suggestions. Certainly, there is a lot of advanced material here. There has been a lot of work done on the aldol reaction the last thirty or so years, and what you see here is really just the tip of the iceberg. I agree that the article could perhaps be restructured to be more inviting to the average reader; however, I wonder if people might suggest, more specifically, what more basic material ought to be in the article? I didn't include some of the standard sophomore stuff like the intramolecular aldol stuff...

As for sub-articles, I must say I oppose such an idea. I don't really see the advantage of that, and some logical flow could be lost. A prior discussion of enolate geometry is essential to a discussion of aldol stereocontrol. The diastereoselectivity of the aldol will lead naturally into a discussion of the Evans' auxiliary method. Now, the article may become quite long, but perhaps this will not be such a big problem if everything is sectioned properly and if the most basic information can be summarized at the beginning.

As far as extra topics to be included, I felt that discussions of the Mukaiyama aldol would really lengthen the article, and frankly, be a lot of work. One might feel forced to cover the methods of generating silyl enol ethers, and then the geometry of said ethers, and then move on to other "aldol surrogates" like metalloenamines, which are a whole topic on their own. We should probably decide to limit the discussion somehow...

I suppose any discussion of the aldol reaction, beyond the basic points, is necessarily technical. I appreciate that Wikipedia is not a technical manual, but I really think what we've covered here is not terribly beyond what a typical Ph.D. organic chemist knows. And I see no reason why a junior or senior major in chemistry couldn't use what's here to write an in-depth report or something. I think it's nice to have a relatively simplified view of the aldol reaction condensed in one place. Eugene Kwan 07:02, 29 December 2005 (UTC)

    • I restate my comment that the article contains too much jargon and is too technical. This should not mean that material gets thrown out. In my view Wiki articles cannot be too technical if the underlying principles are worked out. The current article lacks many links.
  1. Links to concepts that should be included: Nucleophilic addition
  2. concepts mentioned in the text but not linked: antiperiplanar chair conformation chemical equilibrium diethyl malonate benzaldehyde methylene malonate sodium ethoxide Stereoselective olefin hyperconjugation Stoichiometry bond length diastereoselectivity chirality stereocenter epimer Pentane interference rotamer links to these articles will really help the average reader
  3. concepts mentioned in text but not explained pi* orbital triphenylmethyllithium 9-BBN-Cl, DIPEA, Cy2BCl 1,3-diaxial interaction allylic 1,3-strain diastereoface polyketide stereoarray

Also many Aldol variations are already contained in separate articles (5 other variations branch of in the aldol condensation reaction alone) so I have no problem with subarticles for variations. V8rik 20:03, 29 December 2005 (UTC)

Sure, there are many links missing. But I thought it prudent to leave them out until much of the text is fleshed out. I think it's rather unreasonable to expect every concept to be explained, at least within the aldol article. There's really no reason to discuss what a pi* orbital is or what allylic strain is. Perhaps Wikipedia ought to have stuff on it, but at any rate, anyone interested in the more advanced sections has surely heard of those. Also, I don't think reagents like 9-BBN-Cl are really "concepts". If they are mentioned in the text, they're in some sort of example... Who is this "average reader"? How much chemistry background does one expect him or her to have? I'm sort of new to this. Eugene Kwan 20:24, 29 December 2005 (UTC)

Just a few points:
1) Don't worry about the missing links. They will get filled in.
2) Don't worry about explaining every concept. They will get explained eventually.
3) Don't worry about explaining every reagent. Once again, they will get their own pages eventually.
4) The page is so far geared towards the "average organic chemist with a PhD". I like it that way. We must also include the "average undergrad" who has just learned in O-chem class what the aldol reaction is. We will work on that. Walkerma has said he has some ideas. I wouldn't worry about this.
5) My advice: Just write the page how you think it should be written. If it's the truth then it will stick.
This is shaping up to be a fantastic article. I look forward to seeing it's completion. ~K 01:16, 30 December 2005 (UTC)

Hey, thanks. That is reassuring. I do strive for accuracy, but it is a complicated topic... Eugene Kwan 06:21, 30 December 2005 (UTC)

K is absolutely right, I couldn't have put it better. Keep up the good work! Walkerma 16:47, 30 December 2005 (UTC)

Evans Aldol

I've added a lot of stuff on the Evan's aldol. I'm going to add some stuff on the catalytic, asymmetric methods available, and give an example or two in total synthesis, and then that'll probably be the bulk of my contributions... As always, your feedback is appreciated. Eugene Kwan 23:55, 1 January 2006 (UTC)


Common Format

Hi everyone, not to be a bother or anything, but do you think we might stick to a common chemical structure format? I've been using the ACS template with no explicit hydrogens unless necessary... Also, do you think the intro scheme and the enol/enolate scheme I put in are sort of similar? Eugene Kwan 05:22, 5 January 2006 (UTC)

Hi Eugene. Yes, your scheme and mine are quite similar, I plagiarised yours shamelessly! I hope that on Friday to post a rewrite of that section so the duplication will disappear, but I don't think it's a serious problem for a temporary situation as there are significant differences. I wanted to get the intro up fairly quickly. As for format, I think your format is the right one for the bulk of the article, but for the intro I think it's better to include hydrogens. Many undergraduates have a hard time understanding line-angle formula; for this reason most textbooks (such as Wade that I cite) show hydrogens explicitly when explaining the basics, but they use line-angle in many questions & examples. Is it a problem to do our schemes like in Wade? I think the only other scheme I plan to revise is the mechanism scheme, which I plan to break into two parts as I want to describe the mechanisms explicitly. By the way, I loved your definition of the aldol; I struggled with this for a while for the intro, then noticed yours in the text that followed, better than anything I could think of! Walkerma 06:28, 5 January 2006 (UTC)

Well, I guess that's OK. The hydrogens reduce some of the aesthetics of the introduction, that's all. Maybe we could have a nice looking scheme for the "teaser" bit of the article, and then a more detailed one for the introduction, which is presumably targeted at say, the "uninformed undergraduate". Eugene Kwan 02:27, 6 January 2006 (UTC)

Now that the errors have been fixed, should we update the external peer review/nature errors page? I'm not sure how to do that. Eugene Kwan 02:29, 6 January 2006 (UTC)

I did that a while ago. ~K 04:24, 6 January 2006 (UTC)

Question on example used

I am working on mechanism schemes (offline, in ACS format Eugene!), trying to tie things in with the later article. We show propiophenone and acetophenone reacting to give an aldol product, but based on what I know of ketone equilibria and aldol thermodynamics this reaction is unlikely to go to any significant extent. Am I wrong (maybe because of the aryl group)? Or should we consider having two aldehydes for the crossed aldol example? Wade uses acetaldehyde and propionaldehyde, this example is often used I think. Please let me know your thoughts, thanks, Walkerma 07:04, 6 January 2006 (UTC) By the way I fixed a couple of things in the intro scheme. Walkerma 07:18, 6 January 2006 (UTC)

Well, to be honest, I just made up that reaction. It's not really a reaction you'd want to try, anyways. I only meant to use that to illustrate the problem of multiple products. I suppose we could find a real example... Eugene Kwan 07:41, 6 January 2006 (UTC)

Evans' chiral oxazolidone edit

I removed part of the end of 5.1 Evans' Oxazolidone Chemistry which discusses stereoselective β-hydroxyketone reduction. It was off-topic, and as the section was getting longish, it seemed a good way to trim the article. However, if others feel I'm wrong, the text is still in the database and can easily be put back in the article. ~K 21:22, 7 January 2006 (UTC)

Perhaps I should have made this clear, but I think it's pretty important, because if you don't reduce the imide aldol adduct, and you try to cleave the auxiliary, then you lose a stereocenter. I should probably have mentioned that allylic strain is what preserves all these stereocenters under such basic conditions. Also, these imide aldol adducts allow you to get what amounts to anti aldol adducts without actually doing an anti aldol. Eugene Kwan 03:41, 8 January 2006 (UTC)

I see what you're saying. I think if you put that clarification in the article, then knuckleheads like me would follow you better. ~K 05:43, 8 January 2006 (UTC)

No, no, it's my fault, it wasn't clear at all. Eugene Kwan 05:56, 8 January 2006 (UTC)

Direction for Article

Hi guys, Sorry I haven't had time to work on the article. I was just wondering where we want to take article from here? As I mentioned before, it'd be cool if we could get it up to "featured article" standards... Eugene Kwan 22:21, 20 January 2006 (UTC)

Here's what I think.
  1. We finish the article.
  2. We get other chemists from WP:Chemistry to evaluate the article.
  3. We submit the article for Peer Review.
  4. We submit the article to Featured Article Candidates.
  5. We bask in the glory of a featured article.
~K 03:21, 21 January 2006 (UTC)
I agree with ~K, though before we do any basking we need to agree on what is needed for #1. Obviously there are the two empty sections at the end. I can also accept Eugene's comment about keeping the Mukaiyama aldol on a separate page, though IMHO we should have a short page on it before making the main aldol an FAC. For myself, I would also like to do a bit of clarification on the crossed aldol problem, and I think we need to make clear the main selectivity issues:
    • Chemoselectivity (the crossed aldol- which C=O reacts as the electrophile?)
    • Regioselectivity (where will the enolate form? kinetic vs thermodynamic etc.)
    • Diastereoselectivity (E vs Z enolates)
    • Enantioselectivity (Evans and other methods)
Any thoughts? Other things we need to do? Walkerma 04:22, 21 January 2006 (UTC)

I still need to fix up the end of the Evans' aldol section, add a bit on catalytic, enantioselective methods, and put in a bit on practical applications in total synthesis. I could add a little on the Mukaiyama aldol too. I'd welcome any clarification on the selectivity issues, although I'm unclear as to what exactly needs clarification... Perhaps to get a featured article, we need a snazzy picture? I'm not sure what such a picture would be, however. Eugene Kwan 05:21, 21 January 2006 (UTC)

I think the reaction schemes help break up the text somewhat, but one or two photos would spice it up nicely. Could you take a picture of an aldol rxn going on in a (tidy) fume hood - perhaps syringing in something into a stirred rb flask? I'm not likely to be running an aldol any time soon, at least not until August. Also, it would be really nice if we could get a nice picture of David A. Evans, but only if he's amenable to such a thing. Walkerma 06:20, 21 January 2006 (UTC)

NPOV

"The aldol reaction is an important carbon-carbon bond forming reaction in organic chemistry[1][2]"

Importance is inherently subjective. If the cited articles claim that the reaction is important, the article should make it more clear that the opinion (as well as the fact that the reaction is a carbon-carbon bond forming reaction in organic chemistry) comes from the articles. However, I suspect it would be far better to rework the sentence/paragraph to show that the reaction is important, rather than saying that the reaction is important. --Dfeuer 02:11, 25 January 2006 (UTC)

I'm not sure how the policy applies to this situation, but this is a widely regarded opinion. Would it be improper to say that nuclear fission is an important way of generating power, or that applying paint to canvas is an important way of making art? If you want to make C-C bonds in organic chemistry, this is a really important way of doing it. Oh, and apologies for the continuing delay...things are ridiculously busy in the lab now. Eugene Kwan 03:28, 25 January 2006 (UTC)

I think it would be equally improper to say that nuclear fission is an important way of generating power or that applying paint to canvas is an important way of making art. An anti-nuclear activist would likely dispute your assertion that nuclear fission is important. Paint on canvas is an important form of art for many people, but it is unimportant to blind people and people whose cultures emphasize other art forms or even lack works of paint and canvas altogether. Importance always requires context. Dfeuer 07:00, 25 January 2006 (UTC)

Even a nuclear activist would agree that nuclear power is an important method of generating power, if not a prudent one. It doesn't matter that some people can't or won't appreciate paintings as art; since most people do, paintings qualify as an important form of art. The context is implicit here: organic synthesis. Any reasonable, informed person would agree that the reaction is an important way of making C-C bonds. I don't think there's much "opinion" to it.

In terms of the spirit of the policy, no one is advocating the use of the aldol reaction here, and nor is it biased in favor of it (e.g. the aldol reaction is a better C-C bond forming reaction than alkylation). This is like saying "cars are an important form of transportation"--nothing is being said for or against cars. It is left up to the reader to decide, for example, what is a good reaction and what is not. Eugene Kwan 20:11, 25 January 2006 (UTC)

"Since most people [appreciate paintings as art], paintings qualify as an important form of art." Painting is considered an important form of art in western culture. In large parts of the world, it is insignificant. Dfeuer 03:35, 28 January 2006 (UTC)

This is not simply an opinion! One can check the references, which confirm that the reaction is indeed important, based on the fact that at both the basic level (Wade) and the more advanced level (March) a lengthy description is given for the reaction and its uses (March gives 58 references). Moreover, this type of introduction is a standard style used in chemistry. Finally, the fact that Nature chose to review this topic is also an indication of its importance. Walkerma 20:33, 25 January 2006 (UTC)

The only reason I can see for claiming that the reaction is important is to convince someone to read the article about it. While this is very common in textbooks and scientific articles, it is not good style. If someone looks up Aldol reaction in Wikipedia, they do so because they already think it's important enough to learn something about. I would venture a guess that it would be just as sensible to have nearly every article in Wikipedia claim that its topic is important. Dfeuer 03:23, 28 January 2006 (UTC)

I say "important" because there are reactions of various levels of importance. I would say the aldol reaction is very important, whereas the Eglington coupling (two terminal alkynes, copper) is of marginal importance. However, I wouldn't object if someone took out "important". Eugene Kwan 06:07, 28 November 2006 (UTC)

Errors in the 'Matched/Mismatched' section

The 'matched case' and 'mismatched case' show the same aldehyde, though the transition states are drawn with their enantiomers. (Presumably, the enantiomer of the 'matched case' aldehyde should be shown.) The referenced JACS article (1995, 117, 9073) does not contain the reaction in the image, although it is similar.

Yes, I thought I had explained that, but I think I might have left it out. The real reaction done is with the same aldehyde, but to show the model more clearly, I drew the enantiomer of the aldehyde. As for where the reaction came from, I got it from the Chem 206 notes (www.courses.fas.harvard.edu/~chem206; Aldol lecture 2), and I just put in the reference that was given. I'm a little puzzled as to where that example is from now. Suggestions? Eugene Kwan 01:04, 22 February 2006 (UTC)

New Picture

I took a picture today of my aldol reaction. I'm not sure how you make it smaller, so please, reformat, reformat! Thanks. Eugene Kwan 20:13, 28 February 2006 (UTC)

OK, someone helpfully resized it. How do I move the caption? It's now stuck in the middle of the text. Eugene Kwan 20:45, 28 February 2006 (UTC)

Sorry I missed the caption. I have moved it now. There's quite a bit of whitespace right now (at least in my browser) so maybe things need to be shuffled around a bit. Edgar181 20:53, 28 February 2006 (UTC)