The invention discloses a preparation method of 3, 3, 3-trifluoro-1-
propyne, which comprises the following steps: (1) taking E-1-chloro-3, 3, 3-propylene as a
raw material, and carrying out
chlorine or
bromine addition to obtain a compound as shown in a formula (I); (2) in a first
solvent, in the presence of alkali, the compound shown in the formula (I) is subjected to an
elimination reaction to obtain 1, 2-diX-3, 3, 3-trifluoropropene shown in the following formula (II) and / or 2-X-1-chloro-3, 3, 3-trifluoropropene shown in the following formula (III), X is
chlorine or
bromine, when X is
chlorine, the structures of the formula (II) and the formula (III) are the same, and the formula (II) and the formula (III) are 1, 2-dichloro-3, 3, 3-trifluoropropene; and (3) in a second
solvent, in the presence of a
reducing agent, carrying out
elimination reaction on the compound as shown in the formula (II) and / or the formula (III) to obtain the 3, 3, 3-trifluoro-1-
propyne. According to the method, the trifluoropropyne is prepared by taking E-1233zd as a
raw material, the technical problems of low conversion rate and poor selectivity in the process of preparing the trifluoropropyne through an E-1233zd
raw material route are solved, the raw materials are easy to obtain, the cost is low, the method is very suitable for industrial application, and the market competitiveness of the product can be greatly improved.