1: 1) NaH / 1) DME, 2h, RT, 2) 0.5 h 2: NaBH4 / H2O; ethanol / 2 h / Ambient temperature View Scheme

Multi-step reaction with 3 steps 1: 1) n-butyllithium / 1) hexane, THF, -40 deg C, 4 h, 2) warm to RT, 12 h2: 2) iodine / 1) dirhodium tetraacetate / 1) 18 h, 2) CH2Cl2, RT 6 h3: 1) aluminium hydride, 2) pyridinium dichromate