2-Hexenoic acid, 5-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-,(1R)-2-[(4R,5R)-5-[(1E)-3-methoxy-3-oxo-1-propenyl]-2,2-dimethyl-1,3-dioxolan-4-yl]-1-methylethyl ester, (2E,5R)-