Efficient one-pot preparation of 6-methylsulfanyl-5-phenyl-2,3-dihydro-1H-pyrrolizine from 2-tert-butylsulfanyl-3-phenyl- or pyrrolidin-1-yl-cyclopropenethiones
Abstract
The one-pot reaction of 2-tert-butylsulfanyl-3-phenyl- or pyrrolidin-1-yl-cyclopropenethiones 1 and 2 with lithium pyrrolidinide or phenyllithium at –70 °C, followed by methylation with methyl iodide, gives 6-methylsulfanyl-5-phenyl-2,3-dihydro-1H-pyrrolizine 3 in a high yield.