1: carbon dioxide; C20H26ClNO2Si With cesium fluoride in N,N-dimethyl-formamide T=20°C; P=760.051 Torr; 1 h; 2: diazomethane With N-methyl-N'-nitro-N-nitroso-guanidine; potassium hydroxide in diethyl ether; water T=0°C; 0.166667 h;