Electro-organic transformation of indoles to bis(indolyl)methanes (BIMs) has been successfully achieved by combining the electrochemical alcohol oxidation reaction (AOR) with indole coupling. The fact that it is the readily available alcohols and not the traditionally used aldehydes or ketones that provide the bridging -CH2- (methylene) for this transformation makes this path extremely attractive and valuable. The formation of aldehydes as reactive intermediates during the AOR has been dexterously utilized to achieve this transformation. Most gratifyingly, the transformation also can be carried out in water-alcohol mixtures and the yields and conversions are better than the most of the previously reported chemical catalytic transformations using specially designed metal complexes. Various substituted indoles were selectively converted to their corresponding BIMs in decent yields. This strategy could further be exploited for the synthesis of different natural products, including the much sought after deuterium substituted ones (as CD3OD is readily accessible), and other important biologically active alkaloids and drug molecules, etc.

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