Oxazolidinium salts

A review of diastereoselective additions of organometallics to chiral oxazolidines has appeared (94MI99). The Diels-Alder reaction of (R)-2-phenyl-4-methyleneoxazolidin-5-one 59 with 2,3-dimethylbutadiene proceeds with exo-diastereoselectivity to yield the adduct 60 (94T941). The action of sodium cyanide on the chiral oxazolidinium salt 61 leads to the cyano ether 62 stereoselectively (93TL8325). 

From Thiirans. The synthesis of oxazolidinium salts from oxirans has been supplemented by that of thiazolidinium salts from thiirans (Scheme j7) 219 Thus, thiiran (295) reacts with dimethylchloromethylamine (296 ... 

Oxazolidinium from aziridinium salts Ring expansion... 

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