a Reagents and conditions: (a) (Carbethoxymethylene)triphenylphosphorane, benzene, reflux, 74%; (b) DIBAL-H, CH2Cl2, −78 °C to 0 °C, 93%; (c) cumene hydroperoxide, (+)-DIPT, Ti(OiPr)4, 3Å molecular sieves, CH2Cl2, ,−40 °C, 79%; (d) NaH, benzyl bromide, TBAI, THF, rt, 1 h, 96%; (e) NaN3, NH4Cl, 2-methoxyethanol–water 9:1, reflux; (f) NaH, benzyl bromide, TBAI, THF, rt, 1h, 78% over two steps; (g) LiAlH4, THF; (h) tosyl chloride, triethylamine, CH2Cl2, rt, 90% over two steps. (i) 2N HCl: methanol, 40 °C; (j) TBSCl, triethylamine, DMAP, CH2Cl2, 85% over two steps; (k) triphenylphosphine, DIAD, CH2Cl2, rt; (l) Na, naphthalene, DME, −60 °C, 60% over two steps; (m) aldehyde (butyraldehyde or nonyl aldehyde), sodium triacetoxyborohydride, ClCH2CH2Cl, rt, 70% and 72% respectively over two steps; (n) TBAF, THF, rt; (o) PdCl2, H2, methanol, 65% and 70% respectively.