B. Alcaide et al., HEXACARBONYL DICOBALT COMPLEXED N-PROP-2-YNYL-2-AZETIDINONES - A NEW ENTRY TO N-UNSUBSTITUTED-BETA-LACTAMS THROUGH A NICHOLAS-TYPE REACTION, Journal of the Chemical Society, Chemical Communications, (5), 1994, pp. 587-588
Sequential one-pot treatment of easily obtained N-prop-2-ynyl-2-azetid
inones with CO2(CO)(8) and DMSO-H2O gives under mild conditions N-unsu
bstituted-beta-lactams in good yields and with total retention of ster
eochemistry.