Flash vacuum pyrolysis of alkoxycarbonyl/sulfinyl stabilised phosphorus ylides: generation and intramolecular insertion of alkoxycarbonyl(sulfenyl)carbenes
作者:R. Alan Aitken、Martin J. Drysdale、Bruce M. Ryan
DOI:10.1039/c39940000805
日期:——
Flashvacuumpyrolysis of phosphorus ylides stabilised both by ester and sulfinyl groups results mainly in extrusion of Ph3PO to generate alkoxycarbonyl(sulfenyl)carbenes; these undergo intramolecular insertion into CH of the alkoxycarbonyl group giving β-lactones which under the conditions lose CO2 to afford alkenyl sulfides.
Syntheses of 2-Azetidinone (β-Lactam) Ring by Chlorosulfonyl Isocyanate (CSI)
作者:KOICHI HIRAI、HIDEBUMI MATSUDA、YUKICHI KISHIDA
DOI:10.1248/cpb.21.1090
日期:——
Attempts were made to prepare sulfur substituted 2-azetidinones by the reaction of vinylsulfide with chlorosulfonyl isocyanate (CSI). The main product of the reaction of β-methylthiostyrene (I) with CSI was pyridone derivative (II), but in the case of 1-phenylthio-1-propene (V) the main products were dihydrouracil derivatives (VI and VII) and acrylic acid derivatives (VIII and IX). Reaction of 1-p-chloro- or p-methylphenylthio-1-propene (Xa and b) with CSI in dry ether at -30°gave the desired 2-azetidinone (β-lactam) derivatives (XIa and b) in 63 and 66.4% isolated yield respectively.