acetic acid,but-2-en-1-ol

ethyl 3-methylpent-4-enoate

diethyl 2-but-3-en-2-yl-2-methylpropanedioate

diethyl ((Z)-2-butene-1-yl)methylmalonate

ethyl 2-methyl-2-carboethoxy-trans-4-hexenoate