Categories: Synthesis of S-Heterocycles > benzo-fused S-Heterocycles >
Synthesis of thiochromenes
Recent Literature
Amidine-based catalysts, particularly homobenzotetramisole and its analogues,
achieve high enantioselectivities and yields in a reagent-free catalytic
transformation of α,β-unsaturated thioesters into 2-substituted thiochromenes
with carbon dioxide as the only byproduct.
N. A. Ahlemeyer, V. B. Birman, Org. Lett.,
2016, 18, 3454-3457.
A highly enantioselective cascade sulfa-Michael/Julia-Kocienski olefination
reaction between 2-mercaptobenzaldehydes and β-substituted vinyl PT-sulfones
provides a wide range of 3,4-unsubstituted 2H-thiochromenes with excellent
enantioselectivities. This reaction is catalyzed by diphenylprolinol TMS ether
and proceeds through an aromatic iminium intermediate.
A. K. Simlandy, S. Mukherjee, J. Org. Chem.,
2017, 82, 4851-4858.
Tetramethylguanidine (TMG) promotes a cascade thiol-Michael-aldol-dehydration
reaction between 2-mercaptobenzaldehyde and cinnamate esters to provide 2H-thiochromene-3-carboxylate
derivatives with a variety of substituents in high yields.
T. T. H. Nguyen, T. X. Nguyen, T. T. T. Cao, T. H. Dinh, H. H. Nguyen, T. T. T.
Bui, V. P. Pham, D. H. Mac,
Synlett, 2017, 28, 429-432.