Synthesis 2016; 48(23): 4091-4098
DOI: 10.1055/s-0035-1562473
paper
© Georg Thieme Verlag Stuttgart · New York

Diastereoselective Synthesis of Spiro[pyrazolone-4,3′-tetrahydrothiophenes] via a Sulfa-Michael/Aldol Domino Reaction

Uğur Kaya
a   Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: enders@rwth-aachen.de
,
Suruchi Mahajan
a   Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: enders@rwth-aachen.de
,
Jan-Hendrik Schöbel
a   Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: enders@rwth-aachen.de
,
Arto Valkonen
b   Department of Chemistry, Nanoscience Center, University of Jyvaskyla, 40014 JYU, Finland
,
Kari Rissanen
b   Department of Chemistry, Nanoscience Center, University of Jyvaskyla, 40014 JYU, Finland
,
Dieter Enders*
a   Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany   Email: enders@rwth-aachen.de
› Author Affiliations
Further Information

Publication History

Received: 14 June 2016

Accepted: 14 June 2016

Publication Date:
12 August 2016 (online)


Abstract

A new approach for the diastereoselective synthesis of spiro[pyrazolone-4,3′-tetrahydrothiophenes] was developed. The N,N-diisopropylethylamine-catalyzed reaction of arylidenepyrazolones with in situ generated 2-sulfanylacetaldehyde provides the corresponding spiro-heterocycles via a domino sulfa-Michael/aldol reaction in 42–98% yield and 3:2:1 to 20:1 d.r. under mild reaction conditions.

Supporting Information