(Thiolan-2-yl)diphenylmethanol Benzyl Ether-Catalyzed Asymmetric Cyclopropanation of Chalcones

Abstract

We devised a new method for asymmetric cyclopropanation by employing (S)-(thiolan-2-yl)diphenylmethanol benzyl ether as an organocatalyst. Under optimal conditions, an in situ generated sulfur ylide reacts with (E)-chalcones via a Johnson–Corey–Chaykovsky reaction to afford a variety of cyclopropanes in excellent yields and stereoselectivities. This strategy employs low-environmental-risk reaction conditions and reusable catalysts. Hence, it is a green and efficient method for constructing cyclopropane scaffolds.

Exploring the Power of Sulfur, Silicon, and Organocatalysis: Innovative Strategies for Asymmetric Synthesis and Advanced Synthetic Methodology

“…(E)-chalcones under environmentally friendly conditions via Michael-initiated ring-closure reaction (MIRC). 19 Through this reaction, we demonstrated the effectiveness of catalyst 2-Bn in sulfur ylide mediated asymmetric catalysis.…”

“…Continuing our investigation into the applications of chiral sulfide 2-Bn, we further explored its potential in the cyclopropanation reaction between cinnamyl bromide and (E)-chalcones under environmentally friendly conditions via Michael-initiated ring closure reaction (MIRC). 19 Through this reaction, we demonstrated the effectiveness of catalyst 2-Bn in sulfur-ylide-mediated asymmetric catalysis.…”

Examining the Scope of Deriving β-Aryl Enones from Enol Silanes as Ketone Equivalents via Pd(II)-Mediated Sequential Dehydrosilylation and Arylation

“…1 (E)-4-(3-oxo-3-Phenylprop-1-en-1-yl)benzonitrile (11c). 74 The reaction was carried out according to general method A using trimethyl((1-phenylprop-1-en-1-yl)oxy)silane (10a, 200 mg, 0.970 mmol, 1 equiv) and (4-cyanophenyl)boronic acid (2k, 213.8 mg, 1.455 mmol, 1.5 equiv). The crude product was purified by flash column chromatography using silica gel and a gradient of ethyl acetate and petroleum ether (ratio = 20:80) to afford the title product as a white solid (174.0 mg, 77%).…”

Chiral sulfide and selenide catalysts for asymmetric halocyclizations and related reactions

“…3 The catalytic abilities of chiral sulfide organocatalysts were initially investigated via Corey–Chaykovsky-type asymmetric epoxidations (Scheme 1a). 4 Although several chiral sulfide molecules realized the catalysis of highly enantioselective epoxidations 5 and related reactions 6 via the formation of chiral sulfonium ylide intermediates, the types of asymmetric reactions with chiral sulfide catalysts are still limited in comparison with chiral amine-catalyzed asymmetric reactions. In recent years, several research groups have discovered different methods for catalysis via the utilization of chiral sulfide catalysts.…”