Aza-Wittig Rearrangements of N-Benzyl and N-Allyl Glycine Methyl Esters. Discovery of a Surprising Cascade Aza-Wittig Rearrangement/Hydroboration Reaction

作者：Everett Renata K; Wolfe John P^*

来源：Journal of Organic Chemistry, 2015, 80(18): 9041-9056.

DOI：10.1021/acs.joc.5b01286

Treatment of N-(arylmethyl)-N-aryl or N-allyl-N-aryl glycine methyl ester derivatives with Bu2BOTf and (Pr2NEt)-Pr-i effects an aza-Wittig rearrangement that provides N-aryl phenylalanine methyl ester derivatives and N-aryl allylglycine methyl ester derivatives, respectively, in good yield with moderate to good diastereoselectivity. Under similar conditions, analogous substrates bearing N-carbonyl groups are converted to 1,4,2-oxazaborole derivatives. Additionally, N-allyl-N-aryl glycine methyl ester derivatives subjected to similar conditions at elevated temperatures undergo an aza-[2,3]-Wittig rearrangement, followed by a subsequent hydroboration oxidation reaction, to afford substituted amino alcohol products.

• 出版日期2015-9-18