Abstract
A Brønsted acid-promoted sulfuration/annulation reaction for the one-pot synthesis of bis-substituted thiazoles from benzylamines, acetophenones, and sulfur powder has been developed. One C–N bond and multi C–S bonds were selectively formed in one pot. The choice of the Brønsted acid was the key to the high efficiency of this transformation under metal-free conditions.
Highlights
A Brønsted acid-promoted sulfuration/annulation reaction for the one-pot synthesis of bis-substituted thiazoles from benzylamines, acetophenones, and sulfur powder has been developed
The typical procedure for the synthesis of thiazoles involves the reaction of a-haloketones with thioureas/thioamides using catalysts such as cyclodextrin,[8] iodine,[9] silica chloride,[10] baker's yeast,[11] and others[12] (Scheme 1a)
The development of efficient methods for the synthesis of thiazoles from simple and readily available substrates under metal-free conditions is highly desirable. It is well-known that the sulfur element is cheap, stable, and easy to handle and it is an ideal sulfur source for C–S bond construction.[18]
Summary
A Brønsted acid-promoted sulfuration/annulation reaction for the one-pot synthesis of bis-substituted thiazoles from benzylamines, acetophenones, and sulfur powder has been developed. The development of efficient methods for the synthesis of thiazoles from simple and readily available substrates under metal-free conditions is highly desirable. It is well-known that the sulfur element is cheap, stable, and easy to handle and it is an ideal sulfur source for C–S bond construction.[18] In our continuing efforts on using elemental sulfur for the synthesis of sulfur-containing heterocycles under simple conditions,[19] we describe a three-component strategy for thiazole formation from readily available acetophenones, benzylamines, and sulfur powder under metal-free conditions (Scheme 1d).
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.