摘要:

Cyclopropyl‐substituted heteroaryl moieties are present in many biologically active natural products1and synthetic drugs,2so the stereodefined cyclopropyl unit is increasingly being incorporated into molecules for their well‐defined three‐dimensional structure.3Although the introduction of simple cyclopropyl groups into heteroarenes has been reported,4general methods for introducing substituted and stereocontrolled cyclopropyl groups into heteroarenes are still scarce. Recently, the preparation of heteroaryl derivatives using palladium‐catalyzed protocols has attracted the interest of many chemists.5Among these protocols, the Suzuki‐type reaction6is appealing, since boronic acids (or esters) are thermally stable and relatively unreactive to both air and water.The success of cyclopropylboronic acids (or esters) in the cross‐coupling reaction7demonstrated that they were useful reagents to prepare cyclopropyl‐substituted compounds. In addition, enantiomerically enriched cyclopropylboronic acids (or esters) can be readily prepared by several methods.8So the Suzuki‐type reaction between cyclopropylboronic acids and eletrophiles to prepare cyclopropyl‐substituted heteroarenes is considered to be quite practical. Furthermore, by changing the substituent on the cyclopropylboronic acid component, the fat‐solubility of the products can be easily adjusted. This modulation is always very important in pharmaceutical research.The coupling reaction of heteroaryl bromides with cyclopropylboronic acids has been reported by our group,9considering that some heteroaryl bromides are difficult to prepare, the study of the corresponding reaction of hetroaryl triflates to make up for this drawback is necessary. Herein we wish to report the results.

ISSN:1144-0546    

出版商:RSC    

年代:2000

数据来源: RSC