Convenient preparation of (Z)-α-halo-α,β-unsaturated aldehydes: synthesis of a Laurencia flexilis toxin

✍ Scribed by Deb K. Barma; Biao Lu; Rachid Baati; Charles Mioskowski; J.R. Falck

• Book ID: 104095411
• Publisher: Elsevier Science
• Year: 2008
• Tongue: French
• Weight: 217 KB
• Volume: 49
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2008.05.026

✦ Synopsis

The CrCl 2 -mediated two-carbon halo-homologation of aryl, alkenyl, and aliphatic aldehydes with chloral ethyl hemiacetal or bromal affords (Z)-a-chloro-and (Z)-a-bromo-a,b-unsaturated aldehydes, respectively, in good to excellent yields and high stereoselectivity. The utility of this methodology was illustrated by a synthesis of 2-chloropentadec-2(Z)-enal, a toxin isolated from the marine red alga Laurencia flexilis.