lantadene B synthesis

Yield:59157-82-3 98.9%

Reaction Conditions:

with sodium tetrahydroborate in tetrahydrofuran;methanol; for 0.0666667 h;Microwave irradiation;

Steps:

Microwave assisted reduction of Lantadene A and B

General procedure: The 100 mg (0.18 mM) of 1 and 2 were separately dissolved in 2 mL of methanol (1 mL) and tetrahydrofuran (1 mL).
To the reaction mixture, 6.80 mg (0.18 mM) of sodium borohydride was added and subjected for microwave irradiations at 210 W (30%) for 1-4 min.
The reaction was monitored on TLC after every 1 min and was incomplete up to 3 min and at 4 min reaction was completed to afford 3 and 4 respectively.
After completion of reactions dilute HCl solution was added to quench the unused NaBH₄.
The organic solvents were evaporated in rota evaporator and precipitated reduced lantadenes were extracted with dichloromethane (DCM).
The solvent was removed under reduced pressure to give 3 (TLC, petroleum ether:ethyl acetate; 4:1, R_f 0.31) and 4, (TLC, petroleum ether:ethyl acetate; 4:1, R_f 0.28).
The product was recrystallized from methanol.

References:

Tailor, Navin K.;Boon, Hong L.;Sharma, Manu [European Journal of Medicinal Chemistry,2013,vol. 64,p. 285 - 291]