5-(2-Methyl-1,3-dioxolan-2-yl)-2-pentanone → HCID 10975921, compound

Participants

Reaction Steps

To a slurry of methyl triphenylphosphonium bromide (218 g) in anhydrous tetrahydrofuran (1.8 l) cooled to 0° C. is added 1.6 M n-butyllithium (270 ml) and2.6 M n-butyl lithium (37.5 ml). After stirring for 1 hour, 6,6-ethylenedioxy-heptane-2-one (91.3 g) in anhydrous tetrahydrofuran (200 ml) is added dropwise and the mixture stirred for 1.5 hours at room temperature. The reaction mixtures is then filtered and the filter cake washed with ether. The solent is removed via distillation at atmospheric pressure. The crude residue is purified via vacuum distillation to give 6,6-ethylenedioxy-2-methyl-hept-1-ene (33.95 g, 38%) bp 75°@15 mm; nmr (CDCl3,δ), 1.32 (s, 3H, ##STR53## 1.7 (s, 3H, CH3 --C=), 3.92 (s, 4H, OCH2CH2O), 4.67 (bs, 2H, ##STR54##

Provenance & Evidence