tert-Butyl methyl ether → (S)-1-{(3aS,7E,7aR)-7-(bromomethylene)-3a,4,5,6,7,7a-hexahydro-3a-methyl-1H-indene-3-yl}ethanol

Participants

Reaction Conditions

Reaction Steps

(1R)-trans-N,N′-1,2-cyclohexanediylbis(1,1,1-trifluoromethanesulfonamide) (2.3 mg, 0.006 mmol) was placed in a reaction vessel. After replacing the atmosphere with nitrogen, t-butyl methyl ether (0.03 ml) was added thereto and dissolved. To the solution, tetraisopropoxy titanium (0.0177 ml, 0.06 mmol) was added at room temperature, and the resulting mixture was heated at 50° C. for 30 minutes. After cooling to room temperature, dimethylzinc (1.0 M in heptane, 0.12 ml, 0.12 mmol) was added thereto. The obtained reaction mixture was added to (3aR,4E,7aS)-4-(bromomethylene)-3a,4,5,6,7,7a-hexahydro-7a-methyl-3H-indene-1-carbaldehyde (Compound 29: 15.3 mg, 0.06 mmol). After stirring the reaction solution at room temperature for 1 hour, ethyl acetate (30 ml) was added thereto, and the resulting mixture was washed with 2N hydrochloric acid, saturated brine and with saturated aqueous sodium hydrogen carbonate solution, respectively. The organic layer was dried over sodium sulfate, and the solvent was evaporated to obtain the reaction mixture. The reaction mixture was purified by preparative TCL to obtain (S)-1-{(3aS,7E,7aR)-7-(bromomethylene)-3a,4,5,6,7,7a-hexahydro-3a-methyl-1H-indene-3-yl}ethanol (18.4 mg, 100%). The spectrum data thereof agreed with the data described in Example 4.

Provenance & Evidence