Rules of the Day 2-28-07

Click here for today's lecture mechanism sheet

1. Diazomethane reacts with carboxylic acids to give methyl esters in very high yield, driven by the formation of N2.

2. The important carboxylic acid derivatives are acid chlorides, anhydrides, esters, and amides.

3. Amides are interesting functional groups in that the amide nitrogen atom is sp2 hybridized, not sp3 as you might expect. This is because the nitrogen lone pair is delocalized into the carbonyl pi bond. This has very important consequences in that the amide C-N bond does not rotate, and the carbonyl group of amides is less electrophilic than you might think. See the picture of the day for more details.

4. Esters are somewhat like amides, in that the ester O atom is partially sp2 hybridized, it is not fully sp3.

Homework: Begin Working on Homework Problem Set 6. It will be due before class next Wednesday, March 1. Reading: Sections 18.1-18.4 (If you did not already read this) Problems in Book: 18.14 You will not turn these in but they are very helpful to PREPARE for the next lecture.