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CuI-Catalyzed Coupling Reactions of 4-Iodopyrazoles and Alcohols: Application toward Withasomnine and Homologs.

ABSTRACT: The direct 4-alkoxylation of 4-iodo-1H-pyrazoles with alcohols was achieved by a CuI-catalyzed coupling protocol. The optimal reaction conditions employed excess alcohol and potassium t-butoxide (2 equiv) in the presence of CuI (20 mol%) and 3,4,7,8-tetramethyl-1,10-phenanthroline (20 mol%) at 130 °C for 1 h under microwave irradiation. The present method was efficiently applied to the synthesis of withasomnine and its six- and seven-membered cyclic homologs.

SUBMITTER: Usami Y

PROVIDER: S-EPMC8199780 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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CuI-Catalyzed Coupling Reactions of 4-Iodopyrazoles and Alcohols: Application toward Withasomnine and Homologs.

Usami Yoshihide Y Kubo Yumika Y Takagaki Toshiki T Kuroiwa Nao N Ono Jun J Nishikawa Kohei K Nakamizu Ayaka A Tatsui Yuya Y Harusawa Shinya S Hayama Noboru N Yoneyama Hiroki H

Molecules (Basel, Switzerland) 20210602 11

The direct 4-alkoxylation of 4-iodo-1<i>H</i>-pyrazoles with alcohols was achieved by a CuI-catalyzed coupling protocol. The optimal reaction conditions employed excess alcohol and potassium <i>t</i>-butoxide (2 equiv) in the presence of CuI (20 mol%) and 3,4,7,8-tetramethyl-1,10-phenanthroline (20 mol%) at 130 °C for 1 h under microwave irradiation. The present method was efficiently applied to the synthesis of withasomnine and its six- and seven-membered cyclic homologs. ...[more]

PMID: 34199652

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