63661-69-8Relevant articles and documents
Trimethylchromens
Nowakowska,Daszkiewicz,Kyziol
, p. 1542 - 1549 (2007/10/03)
Thermal decomposition of 4-(4-hydroxyphenyl)-2,2,4-trimethylchromane (1) gives 2,2,4-trimelhyl-2H-chromen (2) and 2,2-dimethyl-4-methylenechroman (3). Under influence of hydrochloric acid, 3 isomerizes smoothly to 2. Under similar reaction conditions 2′-hydroxy-2,4,4-trimethylflavan (4) is transformed into 2 and 2,4,4-trimethyl-4H-chromen (5); elimination of the phenol moiety is accompanied with a rearrangement. Opening of the pyran ring with subsequent re-cyclization seems to be more reliable expia nation of this transformation than simple 1-3 migration of the methyl group.