77311-68-3Relevant articles and documents
Synthesis of Two Naturally Ocurring Isobutyrates Related to Thymol
Sanghvi, Y. S.,Rao, A. S.
, p. 952 - 954 (2007/10/02)
7-Acetoxymethylcoumarin (15), prepared by heating 7-bromomethyl-4-methylcoumarin (14) with sodium acetate and acetic acid, on heating with NaOH-ethylene glycol, furnishes 3-hydroxy-4-isopropylbenzyl alcohol (3).Compound (3) has been transformed into diisobutyrate (1) of 3-hydroxy-4-isopropylbenzyl alcohol.Selective methylation of 3 furnishes 4-isopropyl-3-methoxybenzyl alcohol (5), an intermediate for the synthesis of sempervirol.Acylation of 5 gives the naturally ocurring 4-isopropyl-3-methoxybenzyl isobutyrate (2). 4,7-Dimethylcoumarin affords o-isopropenylphenol (7) when heated with aq.NaOH at 140 deg C, but if the reaction is carried out at 210 deg C the product formed is m-cresol (17).
Synthesis of Two Naturally Occuring Oxygenated Oxiranes Related to Thymol
Sanghvi, Y. S.,Rao, A. S.
, p. 1049 - 1051 (2007/10/02)
7-Acetoxymethyl-4-methylcoumarin (3) on heating with aq.NaOH furnishes 2-(2'-hydroxy-4'-hydroxymethylphenyl)propene (5), which has been transformed in two steps to the naturally occuring oxirane, 2-methyl-2-(2'-hydroxy-4'-hydroxymethylphenyl)oxirane diisobutyrate (14).Selenium dioxide oxidation of 2-(2'-acetoxy-4'-acetoxymethylphenyl)propene (7) yields 2-(2'-acetoxy-4'-acetoxymethylphenyl)prop-2-en-1-al (8) which on reduction with NaBH4 and subsequent saponification furnishes 2-(2'-hydroxy-4'-hydroxymethylphenyl)prop-2-en-1-ol (9).The triol (9) has been transformed in two steps into 2-hydroxymethyl-2-(2'-hydroxy-4'-hydroxymethylphenyl)oxirane triisobutyrate (15).An alternative synthesis of 9 is also described.The preparation of o-isopropenylphenol (5) by the action of aq.NaOH alone, instead of NaOH-ethylene glycol, on the coumarin (3) is significant.This modification provides a conveniant route for the preparation of o-isopropenylphenols in those cases where the use of NaOH-ethylene glycol is not satisfactory.