Ch3-ch-ch3+ br2(cв) x1+koh(сп.р.) x2+hbr ch3

C2H4+Br2--->C2H4Br2
CH2Br-CH2Br + 2H2O-->CH2OH-CH2OH(X1)+2HBr
CH2OH-CH2OH--->CH#CH(X2) + 2H2O
C2H2 + H2O-->CH3-CHO(X3)
CH3-CHO + Ag2O-->CH3-COOH(X4)+2Ag
CH3-COOH + CH3OH-->CH3-CO-O-CH3(X5)+H2O