Scheme 2 Reagents and conditions: (i) THF, MeOH, NaBH4, rt, 4 h, 32%; (ii) Mesyl chloride, DCM, Et3N, Et2O, -8 °C, overnight, 20%; (iii) CH3CN, K2CO3, EtOH, MW, 120 °C, 100 W, 90 psi, 10 min, 9.3%.