Efficient synthesis of 17-acetyl-13-(p-bromophenyl)-3-methoxy-11,11-bis(methoxycarbonyl)gona-1,3,5(10)-trienes

► 1,8-bis(Trimethylsilyl)octa-2,6-diene and ethylene ketals afford 1,3-divinylcyclopentanes precursors of D-ring of steroids. ► A four step synthesis of 13-bromophenyl gonatrienes is described. ► (8β,9β,14β)-17β-Acetyl-13β-p-bromophenyl-11,11-di(methoxycarbonyl)-3-methoxygona-1,3,5(10)-triene.