In:
European Journal of Organic Chemistry, Wiley, Vol. 2021, No. 6 ( 2021-02-12), p. 1011-1025
Abstract:
Reactions of a novel propyne iminium salt, N , N ‐dimethyl 3‐phenyl‐1‐trifluoromethyl‐propyne iminium triflate, with electron‐rich heteroaromatic ring systems (furans, thiophenes, pyrroles) are reported. The 1‐CF 3 ‐propyne iminium ion can act as a highly reactive ambident electrophile, giving rise to simple electrophilic heteroaromatic ring substitution products, and as a 1,3‐biselectrophile leading to C 2 +C 3 ‐CF 3 annulation products. Moreover, it is an electron‐deficient alkyne which was found to afford double [2+2] cycloaddition products with 2,5‐dimethylfuran and 2,5‐dimethylthiophene. The obtained molecular structures include CF 3 ‐containing compounds with cyclopenta[ b ]furan, cyclopenta[ b ]thiophene, cyclopenta[ c ]thiophene, cyclopenta[ b ]pyrrole, cyclopenta[ c ]pyrrole, 3 H ‐pyrrolizine, and 1,4‐dihydrocyclopenta[ b ]pyrrole ring systems. Analogous reactions of 1,3(or 1,4)‐phenylenebis(1‐CF 3 ‐propyne iminium) salts with furans, pyrroles or thiophenes in a 2 : 1 stoichiometry lead to phenylene‐tethered condensed heterocycles of the same type.
Type of Medium:
Online Resource
ISSN:
1434-193X
,
1099-0690
DOI:
10.1002/ejoc.v2021.6
DOI:
10.1002/ejoc.202001577
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
1475010-7
