Methanol → HCID 58444103, compound

Participants

Reaction Conditions

Reaction Steps

50 g (150 mmole) 7-(4′-tert-Butyl-phenyl)-2-(2,2-dimethyl-propyl)-indan-1-one were dissolved in 180 ml toluene in a 500 ml—roundbottom flask equipped with a reflux condenser. 6.22 g (1.1 eq.) sodium borohydride were added. Then 26.1 ml (4.3 eq.) methanol were added at 50° C. and the mixture was stirred for 4 h at 50° C. Another 3.11 g sodium borohydride and 10.3 g methanol were added and the mixture was stirred at 50° C. overnight. 2M sulphuric acid was added until the gas evolution ceased. After addition of 100 ml water the layers were separated and the organic layer was washed two times with 2M sulphuric acid and once with a saturated sodium chloride solution. The solvent was evaporated and the crude indanol was dissolved in approx. 300 ml of toluene. After addition of 1 g p-toluene sulfonic acid the mixture was heated to reflux using a Dean-Stark-trap until TLC showed complete conversion (90 min). The solution was washed twice with a saturated NaHCO3-solution, once with water and once with a saturated sodium chloride solution. Drying over magnesium sulphate, evaporation of the solvent and recrystallization from 500 ml ethanol afforded 35.3 g (74%) of the desired indene as white crystals. 1H-NMR (400 MHz, CDCl3): δ=7.47 (s, 4H, aromatic), 7.34 (d, 1H, aromatic), 7.25 (d, 1H, aromatic), 7.16 (t, 1H, aromatic), 6.72 (s, 1H, C═CH), 3.44 (s, 2H, benzylic), 2.36 (s, 2H, CH2-t-Bu), 1.37 (s, 9H, Ph-t-Bu), 0.96 (s, 9H, CH2-t-Bu) ppm.

Provenance & Evidence