In 2005, the ACS Green Chemistry Institute (GCI) and the global pharmaceutical corporations developed the ACS GCI Pharmaceutical Roundtable to encourage the development of green chemistry and green engineering in the pharmaceutical industry. The Roundtable has established a list of key research areas including the direct nucleophilic reactions of alcohols. The substitution of activated alcohols is a frequently used approach for the preparation of active pharmaceutical ingredients. Alcohols are transformed into the reactive halides or sulfonate esters, thereby allowing their reaction with nucleophiles. Although the direct nucleophilic substitution of an alcohol should be an attractive process, as one of the byproducts from the reaction yields water, hydroxide is a poor leaving group that hinders the reaction. Recently, the direct substitution of allylic, benzylic, and tertiary alcohols has been achieved through an SN1 reaction with catalytic amounts of Brønsted or Lewis acids. In this review, the approaches leading to a greener process are examined in detail, and the advances achieved to date in this important transformation are presented.

An organocatalytic stereoselective alpha-alkylation reaction of aldehydes based on C-H activation is presented.

A simple and straightforward method for the preparation of indole-3-carboxylic acids was discovered through the direct carboxylation of indoles with atmospheric pressure of carbon dioxide (CO(2)) under basic conditions. The key for the reaction was found to be the use of a large excess of LiO(t)Bu as a base to suppress the undesired decarboxylation side reaction.

A formal formyl: The organocatalytic stereoselective addition of formyl equivalents to aldehydes (see scheme) tolerates a large variety of functional groups to afford products with high enantioselectivity (92–97 % ee) and good yields (up to 95 %). The benzodithiol group can be easily removed with Raney Ni or metalated with nBuLi, thus giving access to a methyl group or to a wide range of useful intermediates.

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