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[求助]
求助翻译一段话,谢谢
N-Methylindole was found to react smoothly with iodo-benzene providing an excellent yield (96%) of the C-2 ary-lated product. The reaction also worked well with an electron withdrawing substituent such as nitro on the aryl iodide (entry 2). To check the generality of the procedure the system was extended to various azoles including benzo-thiazole, thiazole, benzoxazole, oxazole and triazole (entries 3–11). Benzothiazole was found to react e ciently with both iodo and the less reactive bromoarene providing good yields of the desired product. Also, electron donating groups such as methyl and methoxy at the ortho or para positions of the iodoarene were viable partners under the present conditions (entries 5, 7, and 10). 1-Methyltriazole was found to be arylated selectively at the more active C-5 position (entry 11). We also tested the applicability of this method with other heteroarenes such as benzothio-phene and benzofuran (entries 12–15). However, reaction of benzothiophene was found to be sluggish using the pre-sent catalytic system, while benzofuran was found to react e ciently with both iodo and bromobenzene providing good yields of the desired product. Encouraged with the above results, the system was further extended to the aryaltion of ca eine, as the products are of interest as adenosine receptor antagonists. Ca eine was arylated e ectively under the present conditions providing an excel-lent yield of 60% of product (entry 16). If C–H activation methodology is not used, the synthetic sequence leading to these compounds requires several steps instead of a single step. |
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