Synlett 2010(17): 2677-2678  
DOI: 10.1055/s-0030-1258564
SPOTLIGHT
© Georg Thieme Verlag Stuttgart ˙ New York

3-Methyl-2-Butenal

Claiton Pires Ventura*
Instituto de Química, Universidade Federal de Minas Gerais, UFMG, CEP 31270-901 Minas Gerais, Brazil
e-Mail: xclaiton@gmail.com;
Further Information

Publication History

Publication Date:
30 September 2010 (online)

Introduction

3-Methyl-2-butenal, also known as 3,3-dimethylacrolein, is a very interesting reagent used in addition and cyclo­addition reactions. This colorless, light-yellowish liquid has a pungent odor and is miscible in common organic solvents and water. It is commercially available, but it can also be prepared by oxidation of 3-methyl-2-butenol with H2O2. Kon et al. have reported this reaction with a yield of 91%. [¹]

3-Methyl-2-butenal is an α,β-unsaturated carbonyl compound. This compound has interesting properties that result from the conjugation of the carbon-carbon double bond with the carbonyl group and the two electrophilic sites: The carbonyl carbon and the carbon atom that is in β-position to it. The polarization of electron density makes their β-carbon atoms rather electrophilic. [²]

Various examples of the use of 3-methyl-2-butenal are found in the literature. This reagent has been explored for the preparation of 1,4-dihydropiridines, [³] diene adducts, [4] pyranonaphthoquinones, [5] nitropentanal pyrrole, [6] cyclization precursors, [7] and 2H-chromenes. [9]