We report the activation of oxetanyl, azetidinyl, and thietanyl trichloroacetimidates with 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), which rapidly couple with azabicyclo1.1.0butanes (ABB), following the Schmidt glycosylation strategy. The developed protocol is operationally simple, enabling easy access to a library of medicinally relevant 3,3-functionalized oxetanes, azetidines, and thietanes with N1/C3-functionalized ABB. The practicality of the strategy was demonstrated with more than 50 examples, including gram-scale synthesis. Control experiments revealed that both the trichloroacetimidate group and HFIP were essential for the reaction's success.
Sasmal et al. (Thu,) studied this question.