A synthesis of highly hindered thioketones

✍ Scribed by Paul de Mayo; Gražina L.R. Petrašin̄as; Alan C. Weedon

• Book ID: 104237335
• Publisher: Elsevier Science
• Year: 1978
• Tongue: French
• Weight: 206 KB
• Volume: 19
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)85687-2

✦ Synopsis

Many methods for the preparation of thioketones have been reported' but few possess the advantage of wide applicability. The more general or most commonly used procedures available, viz. treatment of the corresponding ketone with anhydrous hydrogen chloride and hydrogen sulphide', with boron sulphide2 , or with phosphorus pentasulphide', involve acidic reaction conditions and in the latter two cases application of heat. We required the sterically hindered thioketone 1 for photochemical studies3, but found that the corresponding ketone was sensitive to the conditions of these standard methods of thioketone preparation, yielding only decomposition products presumably derived from acid-catalysed rearrangement. We report here a method particularly suitable for the synthesis of 1 and other hindered thioketones from the corresponding ketones which avoids these problems.