[CH3:1][CH:2]([OH:5])[C:3]#[CH:4].[H-].[Na+].C([Li])CCC.Cl[Si:14]([CH3:17])([CH3:16])[CH3:15]>CCOCC.CCCCCC>[CH3:15][Si:14]([CH3:17])([CH3:16])[C:4]#[C:3][CH:2]([OH:5])[CH3:1]
Referring to Flowchart II, 3-butyn-2-ol (formula 21) is treated in step H with sodium hydride in ether at -20° C. and then with 2.0 n-butyllithium in hexane, followed by chlorotrimethylsilane, to produce (+)-4-trimethylsilyl-3-butyn-2-ol (formula 22), which is then reacted in step I with lithium aluminum hydride in ether at reflux for several hours, basified and distilled, to produce (±)-trans-4-(trimethylsilyl)-3-buten-2-ol (formula 23). The reaction in step J of (23) in ether with a mixture of sodium dichromate hydrate and sulfuric acid at <5° C. or below produces trans-4-(trimethylsilyl)-3-buten-2-one (formula 24), which upon distillation with selected solvents gives trans-4-(trimethylsilyl)-2-acetoxy-1,3-butadiene (formula 25).
Loading…
