New facile alkoxycarbonylating agent, alkyl pyrazole-1-carboxylates. The preparation and the utilities
作者:Choji Kashima、Shiro Tsuruoka、Saori Mizuhara
DOI:10.1016/s0040-4020(98)00947-8
日期:1998.12
Alkyl pyrazole-1-carboxylates (2), which were readily prepared from alkyl chloroformate or carbazate in good yields, were provided as the new facile alkoxycarbonylating agents toward the Grignard reagents for the synthesis of one carbon higher carboxylic esters. Also amines were alkoxycarbonylated by 2 to produce the corresponding urethanes even in an aqueous medium. Benzyl 3,5-dimethylpyrazole-1-carboxylate (2d) could be utilized for the Cbz-protection of amino acids and esters in good yield without any racemization. (C) 1998 Elsevier Science Ltd. All rights reserved.
Hueckel; Bretschneider, Chemische Berichte, 1937, vol. 70, p. 2024
作者:Hueckel、Bretschneider
DOI:——
日期:——
The Nitrogenated Allylic System as an Intramolecular Nucleophile: A New Route to Pyrazoles