Efficient Synthesis of Thioesters and Amides from Aldehydes by Using an Intermolecular Radical Reaction in Water

• Published in: Chemistry : a European journal 2005-01, Vol.11 (2), p.719-727
• Main Authors: Nambu, Hisanori, Hata, Kayoko, Matsugi, Masato, Kita, Yasuyuki
• Format: Article
• Language: English
• Subjects: aldehydes; Aldehydes - chemistry; amidation; Amides - chemical synthesis; Cetrimonium Compounds; Esters - chemical synthesis; Indicators and Reagents; radical reactions; Spectrophotometry, Infrared; Spectroscopy, Fourier Transform Infrared; surfactants; thioesters; Water - chemistry
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.200400754

The combination of the water‐soluble radical initiator, 2,2′‐azobis[2‐(2‐imidazolin‐2‐yl)propane] dihydrochloride (VA‐044) and the surfactant, cetyltrimethyl‐ammonium bromide (CTAB), was found to be the most suitable condition for the effective and direct synthesis of useful active thioesters (pentafluorophenyl thioesters) in water. In addition, the direct amidation of aldehydes was achieved by the addition of the amines to the thioesterification reaction mixture in water. The most suitable reaction condition for the effective and direct synthesis of useful active thioesters (pentafluorophenyl thioesters) in water was found to be a combination of the water‐soluble radical initiator, 2,2′‐azobis[2‐(2‐imidazolin‐2‐yl)propane] dihydrochloride (VA‐044) and the surfactant, cetyltrimethyl‐ammonium bromide (CTAB), see also scheme. In addition, the direct amidation of aldehydes was achieved by the addition of the amines to the thioesterification reaction mixture in water.