Stannous Chloride-Mediated Reductive Cyclization−Rearrangement of Nitroarenyl Ketones
作者:Dallas K. Bates、Kexue Li
DOI:10.1021/jo0259921
日期:2002.11.1
Instead, 6-methyl-11a, 12-dihydro-6H-quino[3,2-b][1,4]benzothiazine (3) was produced in excellent yield, presumably via novel Sn (IV)-mediated amidine formation from the initial aniline reduction product. Under identical reaction conditions, 2-(2-nitrophenyl)-thiochroman-4-one (6) produces ethyl 5,11-dihydrodibenzo[b,e][1,4]thiazepin-11-ylacetate (7). A novel semipinacol rearrangement is proposed to account
通过使用标准反应条件将硝基芳烃与SnCl2还原为氨基芳烃,可以以优异的收率生产环化产物。因此,在乙醇中用SnCl 2处理后的4-甲基-2-(2-硝基苄基)-2H-1,4-苯并噻嗪-3(4H)-一(2b)未产生预期的苯胺衍生物。取而代之的是,大概是通过新型的由锡(IV)介导的idine形成反应,以极好的收率生产了6-甲基-11a,12-二氢-6H-喹[3,2-b] [1,4]苯并噻嗪(3)。最初的苯胺还原产品。在相同的反应条件下,2-(2-硝基苯基)-thiochroman-4-one(6)生成5,11-二氢二苯并[b,e] [1,4]噻唑啉-11-基乙酸乙酯(7)。提出了一种新颖的半松果糖重排以解决这种广泛的骨骼重排。苯胺衍生物(14)(由6种经FeSO4.7H2O处理)形成12-乙氧基-11,12-dihydro-6H-6,用乙醇中的SnCl2处理后的12-甲二苯并[b,f] [1,5]