Simple iodoalkyne-based organocatalysts for the activation of carbonyl compounds
Juan V Alegre-Requena1, Alberto Valero-Tena2, Isaac G Sonsona1
1Laboratorio de Organocatálisis Asimétrica. Dpto de Química Orgánica. Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza. C/Pedro Cerbuna 12, 50009 Zaragoza, Spain. raquelph@unizar.es.
Abstract:
A novel approach for the formation of bisindolylmethane derivatives (BIMs) is described as a proof of concept to evaluate the catalytic capacity of iodoalkynes. The use of these derivatives is reported as an example of simple halogen bond-based organocatalyst. This kind of activation has not been used before for the synthesis of bisindolylmethane derivatives 3. Interestingly, the preparation of 3-(1H-indol-3-yl)-1-phenylbutan-1-one (8) has been also achieved for the first time with an iodoalkyne derivative. We prove the efficiency of this family of new catalysts by developing a simple and easy operational methodology, opening the door to the development of alternative catalysts in the area of halogen bond-based organocatalysts.
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