Access to Thiophene and 1<i>H</i>-Pyrrole via Amine-Initiated (3 + 2) Annulation and Aromatization Cascade Reaction of β′-Acetoxy Allenoate and 1,2-Bisnucleophile
作者:Chunjie Ni、MingLi Wang、Xiaofeng Tong
DOI:10.1021/acs.orglett.6b00874
日期:2016.5.6
been developed. When 1,4-dithane-2,5-diol is used as the bisnucleophile partner, the corresponding reaction affords fully substituted thiophene-2-carbaldehyde, which might proceed via the amine-catalyzed (3 + 2) annulation and subsequent oxidative aromatization. The reaction protocol is also applicable to a 2-tosylamino-carbonyl bisnucleophile, wherein the (3 + 2) annulation is followed by 1,2-elimination
已经开发了β'-乙酰氧基烯丙基酸酯和1,2-双亲核试剂之间胺催化的级联(3 + 2)环化和芳构化序列。当将1,4-二烷-2,5-二醇用作双亲核试剂伙伴时,相应的反应会产生完全取代的噻吩-2-甲醛,该取代基可能会通过胺催化的(3 + 2)环合反应和随后的氧化芳构化反应进行。该反应方案也适用于2-甲苯磺酰基氨基-羰基双亲核试剂,其中(3 + 2)环化之后,甲苯磺酰基的1,2-消除和异构化得到1 H-吡咯产物。