Water → Beta-Carotene

Participants

Reaction Steps

In a 50-ml round-bottom flask 2.01 g (purity: 40.9%, 1.15 mmoles) of 1-phenylsulfonyl-4-chloro-1,18-di(2,6,6-trimethyl-1-cyclohexen-1-yl)-3,7,12,16-tetramethyloctadeca-2,7,9,11,13,15,17-heptaene was reacted with 1.0 g (purity: 80%, 11 mmoles) of potassium methoxide in 4 g of toluene at 30° C. for 2 hours. Then water was added to the reaction mixture. The resulting organic layer was separated and washed with water, followed by removal of the solvent, to give 2.58 g (purity: 19.1%, 0.918 mmole, yield: 80%) of a crude β-carotene. To this product 10 g of water was added. The mixture was heat-refluxed for 10 hours and subjected to extraction with toluene to remove organic substances, followed by recrystallization of the residue from toluene-methanol solvent, to give 44 mg of a dark brown crystal. The crystal thus obtained was confirmed to be β-carotene by comparison with standard sample.

Provenance & Evidence