通过Pd(OAc)2催化的Fujiwara-Moritani型反应,通过C-H烯基化与烯烃反应,制得在其α位带有烯烃片段的Dihydro -1,4-噻嗪骨架。该方法是选择性的,可推广到多种烯烃,并且仅需1eq。无需助氧化剂即可制备Ag 2 CO 3。事实证明,CH键的活化很大程度上取决于烯烃的取代,而未稠合的二氢-1,4-噻嗪似乎受硫原子的氧化态影响。所得烯烃的效用通过与非稳定的甲亚胺叶立德进行偶极环加成反应得到了证明。
Photochemistry of phthaloylcysteine, its methyl ester and C-unprotected S-alkyl derivatives
作者:Axel G. Griesbeck、Joachim Hirt、Wolfgang Kramer、Paul Dallakian
DOI:10.1016/s0040-4020(98)00063-5
日期:1998.3
cysteine derivatives 1a-d were photochemically transformed by elimination, decarboxylation, and via electron transfer cyclization to the products 2,3,4 and 6–8. The spin selectivities of singlet and triplet pathways were investigated in acetonitrile and acetone. The excited singlets were prone to elimination and γ-H abstractions (e.g. formation of 5) whereas the triplets cyclized to thiazinoisoindoles