1: With n-butyllithium; diisopropylamine in tetrahydrofuran T=-78°C; 0.5 h; 2: 2-methylpropanoic acid methyl ester in tetrahydrofuran T=-78°C; 0.75 h; 3: Caprylic Aldehyde in tetrahydrofuran T=-78 - 20°C; 18 h;

molecular sieve in tetrahydrofuran T=60°C;

1: 1,1-Dimethoxyoctane; Caprylic Aldehyde With (2,7-dimethyl-1,8-biphenylenedioxy)bis(dimethylaluminum) in dichloromethane T=-78°C; 0.0833333 h; 2: [(1-methoxy-2-methyl-1-propenyl)oxy]trimethylsilane in dichloromethane T=-78°C; 3 h; 3: With hydrogenchloride in dichloromethane