1: Z-3-chloro-4,4-dimethyl-2-pentenal With sodium sulfide in DMF (N,N-dimethyl-formamide); water T=20°C; 0.833333 h; 2: bromoacetic acid methyl ester in DMF (N,N-dimethyl-formamide); water T=20°C; 1.5 h; 3: With hydrogenchloride in DMF (N,N-dimethyl-formamide); water 1 h;

trichlorophosphate in DMF (N,N-dimethyl-formamide) T=0 - 75°C; 4 h;

1: N,N-dimethyl-formamide With phosphorus pentachloride T=25°C; 2 h; 2: 3,3-dimethyl-butan-2-one T=0 - 36°C; 3: With water; sodium hydrogencarbonate optical yield given as percent dediastereoselective reaction;

hydrogenchloride in diethyl ether T=0 - 5°C; 2 h;