2,2-Dimethyl-1,3-dioxane-4,6-dione → HCID 14623201, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 2.40 g (5.0 mmol) of Meldrum's acid adduct i.e. rac.-5-[2-[3,4-dihydro-2,5,7,8-tetramethyl-6-phenylmethoxy-2H-1-benzopyran-2-yl]-1-hydroxyethylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione and 1.19 g (6.0 mmol) of alcohol (2RS,3E,6R)-6,10-dimethyl-3-undecen-2-ol in 4 ml of dry toluene was degassed by 3 cycles of evacuating/purging with argon and then heated under argon to 100° C. CO2 evolution started at ca 90° C. and ceased after ca. 30 minutes. The light yellow solution was stirred for another 2 hours at 100° C. The cooled solution was diluted with hexane, washed with water, sat. NaHCO3 solution and brine, dried over Na2SO4, filtered and evaporated to leave 3.6 g of a brown oil. Chromatography on 250 g of silica gel (hexane/ethyl acetate 5% --6%) afforded 2.33 g (81%) of [2R,S)-3-oxo-4-[3,4-dihydro-2,5,7,8-tetramethylβ-oxo-6-(ohenylmethoxy)-2H-1-benzopyran-2-yl-butanoic acid-1,5,9-trimethyl-2-decenyl ester as a colorless very viscous oil.

Provenance & Evidence