Ch3-ch2-ch2oh-(h2so4 t)-> x1-(cl2)-> x2-(koh(спирт. р-р),изб)-> x3-(c акт,t)-> x4-(br2,fe)-> x5

CH3-CH2-CH2-OH+H2SO4=CH3-CH=CH2+H2O
CH3-CH=CH2+CL2=CH3-CH-CL-CH2-CL
CH3-CH-CL-CH2-CL+KOH=CH3-C≡CH
CH3-C≡CH+C= C6H3(CH3)3
C6H3(CH3)3+Br2=C6H2(CH3)Br+HBr