反应详情

LDA (2M in Heptane/THF/ethylbenzene, 48.5 ml, 97 mmol) was mixed with 100 ml THF at −78° C. and stirred for 5mins. (2S,4S)-1-tert-butyl 2-methyl 4-(tert-butyldimethylsilyloxy)pyrrolidine-1,2-dicarboxylate (14 g, 38.92 mmol) in 80 ml THF was added dropwise at −78° C. The mixture was stirred at −40° C. for 1 hr. Then the mixture was stirred at −78° C. for 10 mins. MeI (4.85 ml, 77.8 mmol) was slowly added and the mixture was stirred from −78° C. to r.t. overnight. The mixture was diluted with ether and quenched with 5% HCl. The organic layer was separated and washed with NaHCO3, brine, dried over MgSO4 and concentrated. 18.5 g of crude product as a diastereomeric mixture at C-2 was obtained.

1. stirringThe mixture was stirred at −40° C. for 1 hr
2. stirringThen the mixture was stirred at −78° C. for 10 mins
3. stirringthe mixture was stirred from −78° C. to r.t. overnight
4. customquenched with 5% HCl
5. customThe organic layer was separated
6. washwashed with NaHCO3, brine
7. dry with materialdried over MgSO4
8. concentrationconcentrated