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Please supply reaction scheme images for your favorite reactions. I need some good examples to illustrate (using Reaxys) how a given functionality is converted into another functionality and which protocol I need to use so that a third functionality remains stable during the reaction (the use of free sites and generic groups etc). The examples shouldn't be too basic or too complex. I don't have access to a modern organic chemistry textbook.

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@Bill, thanks for the question. You might get a better response by re-phrasing the question in terms that relate to experimental chemistry. It sounds like you're asking for some examples of reactions to use in your training, no? How about something like "What's your favorite preparative organic reaction?" In the body, you could ask for images of the reaction scheme. Just one idea. Don't worry, everything can be edited on this site, so feel free to give it a try. – Rich Apodaca Nov 18 at 18:31
@Bill, you should see an "edit" link under your question. Just click on it and you'll be able to change the title and body of your question as many times as you like. If for some reason you can't, feel free to use the 'feedback' link at the top of this screen, or here: feedback.chempedia.com – Rich Apodaca Nov 18 at 18:53

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My favourite reaction is the Corey-Fuchs reaction for the conversion of aldehydes to acetylenes. The abstract from the publication as I can't draw the reaction here! "Aldehydes were treated with CBr4 to give RCH:CBr2, which with BuLi or Li-Hg gave RC≡CLi; treatment of RC≡CLi with CO2 or H2O gave RC≡CCO2H (I) or RC≡CH (II), resp.  Thus, 1 equiv Me(CH2)6CHO was treated 1-2 hr at 23° with a reagent prepd. from 2 equiv each of CBr4, Ph3P, and Zn in CH2Cl2 to give Me(CH2)6CH:CBr2, which 1 hr at -78° and 1 hr at +25° with BuLi in THF gave Me(CH2)6C≡CLi; carbonation or hydrolysis gave I [R = Me(CH2)6] and II [R = Me(CH2)6], resp.  Similarly prepd. were I (R = Ph and 3-cyclohexen-1-yl), II (R = same) and III." I have used it many times in natural product synthesis, and it works beautifully.

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@quintus - good one. To help others who may find your answer, could you add a link to your preferred description of the procedure, e.g.: dx.doi.org/10.1016/S0040-4039(01)94157-7 The wikipedia article also has some reaction schemes you might be able to re-use here: en.wikipedia.org/wiki/Corey-Fuchs_reaction . Not necessary, but might give others a faster way to find out more. If you've seen variations in the procedure, asking a separate question about them might also be helpful. Just ideas. BTW, thanks for the contributions! – Rich Apodaca Mar 15 at 16:17
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My vote would be direct reductive amination for the preparation of secondary and tertiary amines:

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My favorite procedure is the one published by Abdel-Magid and coworkers using sodium triacetoxyborohydride at room temperature in halogenated solvents. It has broad functional group tolerance, works well on large and small scale, doesn't use anything particularly hazardous, accepts a large set of commercially-available inputs, and produces products that are highly relevant to drug discovery.

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here are the reactions involved alt text

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The electrophile can be almost anything, Interesting are the TMS group or a halogen. This leads to an intermediate in the synthesis of discodermolide fragments published by Panek etal in Organic Letters, 2002, 4(14), 2397-2400, 10.1021/ol02613. This leads me to a question which I will ask in a moment:))

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 You should edit your original post to add more content. – Casey Mar 16 at 11:59
@quintus, excellent. I do agree with Casey that editing your original post would be preferred. You should see an edit link for your question when logged in. Not essential, just convenient for everyone else. – Rich Apodaca Mar 16 at 16:21
Yes, I understand, I am still getting used to the site, see how long it took me to embed the pics:)) – quintus Mar 16 at 16:44
@quintus - don't worry about getting everything perfect. This will be a learning process for us all. The fact that you've embedded a reaction scheme is a big step forward. Now we can all see what you're talking about and discuss. – Rich Apodaca Mar 16 at 23:10

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