ORGN 70 |
| Carlos Kleber Zago Andrade, Rafael Oliveira Rocha, Otilie Eichler Vercillo, Wender Alves Silva, and Ricardo Alexandre Figueiredo Matos. Instituto de Química, Universidade de Brasília, Campus Universitário, Asa Norte, C.P. 4478, Brasília, DF, 70910-970, Brazil |
| Oxazolidinones and more recently thiazolidinethiones have reached widespread use in stereoselective organic synthesis as chiral auxiliaries due to their high chiral induction abilities. The most common method of coupling these compounds to the substrates is the nucleophilic attack of their lithium salts (generated by reaction with BuLi in dry THF) to acid chlorides or anhydrides. Although the yields of the acylated products are generally very good, there are some disadvantages associated with this methodology: the reaction is run at –78ºC, using a very strong base in a dry ethereal solvent and in some cases it may require an additional step for the preparation of the activated acylating agent. To circumvent these problems, we describe the simple and efficient coupling of chiral and achiral oxazolidinones and thiazolidinethiones with carboxylic acids, using DCC and catalytic (10 mol%) DMAP, in dichloromethane, at room temperature. The acylated products were obtained in very good yields. |
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New Reactions and Methodology, Metal-Mediated Reactions, Heterocycles and Aromatics
8:00 PM-10:00 PM, Sunday, March 28, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Organic Chemistry |