1: vinyl-magnesium bromide; 4-hydroxybutyraldehyde tert-butyldimethylsilyl ether in tetrahydrofuran T=20°C; 0.166667 h; 2: chloroformic acid ethyl ester With triethylamine in tetrahydrofuran T=20°C; 0.5 h;

1: With ozone in dichloromethane T=-78°C; 2: With triethylamine in dichloromethane T=-78 - 20°C;