Question
Dichlorocarbene can be generated by reacting chloroform and aqueous sodium hydroxide in the presence of one of these species, where it acts as a phase transfer catalyst. For 10 points each:
[10m] Name these nitrogen-containing species. One of these species is formed as an intermediate in the Hoffman elimination by exhaustive methylation, before thermally decomposing into an alkene.
ANSWER: quaternary ammonium salts [or quaternary ammonium compounds or quaternary amines; accept quaternary ammonium cations; accept quats]
[10h] Quaternary ammonium salts are examples of these compounds, which include trimethylglycine. In general, these compounds are characterized by a positively charged functional group that bears no hydrogen atom adjacent to a negatively charged functional group.
ANSWER: betaines [prompt on zwitterions; prompt on ylides]
[10e] Oxaphosphetane likely does not form from a betaine intermediate in this reaction. This reaction uses a phosphonium ylide to convert carbonyls to alkenes.
ANSWER: Wittig reaction
<Science - Chemistry>
Summary
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Data
| I wish it were possible to freeze time so I would never have to watch you retire | Aw we're so sorry to hear that maman died today, she gets five big booms | 0 | 0 | 10 | 10 |
| CLEVELAND, THIS IS FOR YOU! | UBC | 10 | 10 | 10 | 30 |
| throw away your cards, rally in the streets | Thompson et al. | 0 | 0 | 10 | 10 |