Testosterone, rearrangement

Photochemical cyclohex-2-enoneH> bicyclo (3.1.0) hexan-2-one rearrangement irradiation of testosterone acetate, 322 Photochemical rearrangements of cross-conjugated cyclohexadienones and their photoisomers... 

Dehydration to olefins, which sometimes accompanies the reaction of alcohols with DAST [95, 108], is seldom as extensive as with a-fluoroamines (FAR and 1,1,2,3,3,3 hexafluoropropyldiethylamine) but occurs in a few cases to the exclusion of fluonnation, thus, 9a-fluoro-11-hydroxysteroids give 9a fluoro-A -steroids [127, 128] Dehydration accompanied by Wagner-Meerwein rearrangement occurs during the fluonnation of testosterone [129] Intermolecular dehydration to form ethers in addition to fluorides is observed in the reaction of benzhydryl alcohols [104] (Table 6)... 

Testosterone is one of the most important male steroid hormones. When testosterone is dehydrated by treatment with acid, rearrangement occurs to yield the product shown. Propose a mechanism to account for this reaction. 

This ring enlargement was applied successfully to testosterone. In this case the Claisen rearrangement was markedly retarded by the angular methyl group. 

A further route to compounds with an aromatic ring A lies in an unusual acid-catalysed rearrangement of steroidal A -3-ketones. Testosterone (35) is reported to give the 4-methyl aromatic compound (36) with trichloroacetic anhydride in the presence of toluene- -sulphonic acid [178]. The mechanism of this reaction is not clear. 

Ring C aromatization of steroids Treatment of 17a-methyl-A - " "-testosterone (1) with 90%, formic acid under rdlux for 15 hr. results in formation of the rearranged 17,17 -dimethylandrosta-4,8,ll,13-tetraene-3-one (2) in 45% yield. 

A Fannitalia group" reported, without details or yields, that both the a- and j3-epoxides derived from testosterone are rearranged by BFs-etherate in benzene to 4-hydroxy-A -3-ketones. Collins (Australia) made a more detailed study in the cholestane series and found that both the a- and the fi-oxide indeed give the hydroxy-A -cholestene-3-one but that they both yield a second product characterized as 5/8-A-norchoIestane-3-one. TTie latter compound evidently comes from an intermediate /3-keto aldehyde, probably by deformylation during chromatography on neutral alumina. 

The enol toluene-p-sulphonate of testosterone (readily prepared with toluene-p-sulphonic anhydride in DMF) undergoes free-radical rearrangement to the 3-oxo-... 

The Mexican owners of Syntex recruited after Marker s departure George Rosenkranz. Within two years, Rosenkranz succeeded not only in the large-scale production of progesterone, but he also estabhshed the synthesis of the male sex hormone, testosterone, from yam roots. The synthesis starts from 16-dehydro-pregnenolone acetate, which is converted into its oxime Beckmann rearrangement ofthe latter is followed by hydrolysis and yields 5-androsten-3)3-ol-17-one acetate. 

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