Premium
Base‐promoted rearrangements of ester groups in 3a,7a‐dihydroindole‐2,3,3a,4‐tetraester
Author(s) -
Jeon Kyu Ok,
Yu Ji Sook,
Lee Chang Kiu
Publication year - 2007
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570440522
Subject(s) - chemistry , indole test , sodium methoxide , isomerization , derivative (finance) , adduct , dimethyl acetylenedicarboxylate , medicinal chemistry , methoxide , ring (chemistry) , methanol , stereochemistry , organic chemistry , catalysis , cycloaddition , financial economics , economics
Tetramethyl 3a,7a‐dihydro‐1‐methyl‐1 H ‐indole‐2,3,3a,4‐tetracarboxylate which is an 1:2 adduct of 1‐methylpyrrole and dimethyl acetylenedicarboxylate underwent isomerization catalyzed by sodium methoxide to form a 5,7a‐dihydro‐1‐methyl‐1 H ‐indole‐2,3,4,5‐tetracarboxylate, its 5,6‐dihydro isomer, and a ring opening product which is an azonine derivative. Fully aromatized esters such as 1‐methylindole‐2,3,4‐triester, 1‐methylindole‐2,3,4,5‐tetraester and 1‐methyl‐2,3,4,6‐tetraester were also isolated. An indole compound which could be formed by conjugative addition of the methoxide ion was also isolated.