1: 1-(3,4-dihydro-2H-pyran-6-yl)ethanone With potassium tert-butylate in tetrahydrofuran T=0°C; 0.0833333 h; Inert atmosphere; 2: benzaldehyde in tetrahydrofuran 0.5 h; Inert atmosphere; 3: With water in tetrahydrofuran Inert atmosphere;

1: 1-(3,4-dihydro-2H-pyran-6-yl)ethanone With lithium diisopropyl amide T=-40°C; 2: chloro-trimethyl-silane T=0°C;