Trapping highly reactive dipolarophiles. Exploiting the mechanism associated with the azomethine ylide strategy for β-lactam synthesis
作者:Giles A. Brown、Kirsty M. Anderson、Jonathan M. Large、Denis Planchenault、Dominique Urban、Neil J. Hales、Timothy Gallagher
DOI:10.1039/b103271m
日期:——
Highlyreactive thioaldehydes 7, which are generated transiently by thermolysis of thiosulfinates 6, are trapped using azomethine ylide (derived from the β-lactam based oxazolidinone 1) to give 2-substituted penams 8. Diethyl thioxomalonate 10 and the selenoxo analogue 13, both of which are generated transiently via a retro Diels–Alder reaction, undergo 1,3-dipolar cycloaddition reactions with 1 to
KIRBY, GORDON W.;MCGREGOR, WILLIAM M., J. CHEM. SOC. PERKIN TRANS. PT 1,(1990) N1, C. 3175-3181
作者:KIRBY, GORDON W.、MCGREGOR, WILLIAM M.
DOI:——
日期:——
US7381585B2
申请人:——
公开号:US7381585B2
公开(公告)日:2008-06-03
Preparation of cycloaddition chemistry of thio- and selenocarbonyls derived from reaction of elemental sulfur and selenium with stabilized α-halo anions
作者:Matthew M. Abelman
DOI:10.1016/0040-4039(91)80114-l
日期:1991.12
Reaction of diethyl chloromalonate with Cs2CO3 in the presence of elemental S8 or Sen generates the corresponding diethyl thioxo- or selenoxomalonates which are subsequently trapped in situ with various 1,3-dienes. Similarly, the chalcogen carbonyls can be prepared from other halogenated using DBU as the base and effectively trapped in Diels-Alder fashion with 2,3-dimethyl-1,3-butadiene (Table 2).
氯丙二酸二乙酯与Cs 2 CO 3在元素S 8或Se n的存在下反应,生成相应的二乙基硫代肟酸或亚硒酸丙二酸酯,随后将其与各种1,3-二烯原位捕获。同样,硫族化合物羰基化合物可以用DBU作为碱从其他卤代物中制备,并以Diels-Alder方式有效地被2,3-二甲基-1,3-丁二烯捕获(表2)。
Kirby, Gordon W.; McGregor, William M., Journal of the Chemical Society. Perkin transactions I, 1990, # 11, p. 3175 - 3181