title: Steroids 49. Investigations on the dehydration of 17 alpha-ethynyl-17 beta-hydroxysteroids.
abstract: The acidic dehydration of 17 alpha-ethynyl-17 beta-hydroxysteroids (1-3) was investigated. On reaction with thionyl chloride, phosphorus oxychloride, and formic acid, the desired dehydration was accompanied by chlorination, Wagner-Meerwein rearrangement, and D-homoaromatic rearrangement. The structure of the product from the transformation of 17 beta-hydroxypregn-20-yne derivative (3) on reaction with formic acid was misjudged. It was regarded as a pregn-16-en-20-yne (10) instead of the actually rearranged D-homoaromatic compound (11). As a consequence, physical data corresponding to this latter structure have been cited in the literature as those of pregn-16-en-20-yne derivative (10). This confusion prompted us to prepare compounds of both types (4, 9, 10, and 11), the characterization of which is here described.
authors.affiliation: Department of Organic Chemistry, Attila József University, Szeged, Hungary.
authors.forename: I
authors.initials: I
authors.lastname: Vincze
authors.forename: M
authors.initials: M
authors.lastname: Lökös
authors.forename: T
authors.initials: T
authors.lastname: Bakos
authors.forename: A
authors.initials: A
authors.lastname: Dancsi
authors.forename: M
authors.initials: M
authors.lastname: Mák
mesh_terms: D005003:Ethisterone / Q000737:chemistry*; D005561:Formates / Q000737:chemistry; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008656:Mestranol / Q000737:chemistry*; D015394:Molecular Structure; D009640:Norethindrone / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry; D017553:Phosphorus Compounds; D013461:Sulfur Oxides / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D005561:Formates; D007202:Indicators and Reagents; D017553:Phosphorus Compounds; D013461:Sulfur Oxides; D014867:Water; C030544:formic acid; D010758:Phosphorus; C023589:thionyl chloride; C013196:phosphoryl chloride; D008656:Mestranol; D005003:Ethisterone; D009640:Norethindrone