| Abstract
| - Conversion of N-alkyl lactams to the corresponding α-phosphono lactams has been investigatedthrough procedures that involve formation of the lactam enolate and reaction with a phosphoruselectrophile. With N-octylpyrrolidinone, the enolate could be trapped efficiently on oxygen by reactionwith diethyl phosphorochloridate, and the resulting vinyl phosphate rearranges smoothly to thedesired phosphonate upon treatment with additional LDA. Attempts to apply the same protocol toN-farnesyl lactams met with limited success. Studies with an isolated α-phosphono N-farnesyllactam have shown that the farnesyl group is not stable to the excess of strong base required forrearrangement of a vinyl phosphate. However, a series of N-farnesyl lactams and imides wasconverted to the desired phosphonates through formation of the lactam enolate, reaction with diethylphosphorochloridite, and subsequent oxidation of the phosphorus intermediate to the P(V) state.
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