(i) NaHMDS, ICH2CH=CHCH2CH2OBn, THF, 92%; (ii) AD mix β*, NaHCO3, t-BuOH, H2O, r.t., 4 : 1 d.r., 55%; (iii) TIPSOTf, imid. DMF, 88%; (iv) LiBH4, MeOH, THF, 99%; (v) PivCl, DMAP, Et3N, CH2Cl2, 82%; (vi) BnBr, NaH, DMF; (vii) TBAF, THF, 24% over 2 steps; (viii) TESCl, DMAP, Et3N, CH2Cl2, 99%; (ix) LiBH4, MeOH, THF, 89%; (x) TPAP, NMO, CH2Cl2, mol. sieves, 95%.