Preparation method for 3-methyl-3-butene-1-ol

Abstract

The invention discloses a preparation method for 3-methyl-3-butene-1-ol. The preparation method comprises the following steps of causing water, transition metal salt, isobutylene and formaldehyde to enter a condensation reactor, and performing condensation reaction under the conditions of 300 to 360 DEG C and 5 to 25MPa, wherein the transition metal salt is one or two or more of vanadium, chromium, iridium, iron, rhenium, ruthenium, cadmium, platinum, cerium, praseodymium, neodymium, samarium, europium, terbium, dysprosium, thulium and the like, the condensation reaction can be completely implemented within 1 to 100s under the synergistic catalysis of transition metal ions and [H3O<+>], and only a small amount of isobutylene is required; performing light component removal, dehydration and heavy component removal on condensation reaction liquid to obtain high-purity 3-methyl-3-butene-1-ol.

Description

technical field [0001] The invention relates to the field of synthesis of fine chemicals, in particular to a synthesis method of 3-methyl-3-buten-1-ol. technical background [0002] 3-Methyl-3-buten-1-ol is an important intermediate in the synthesis of fragrances, medicines, pesticides, etc.: (1) This substance can be used to synthesize citral, and thus further synthesize L-menthol and ionone , carotenoids, vitamin A, vitamin E, etc.; (2) After being converted into 3-methyl-2-buten-1-ol by hydroisomerization, it can be used to synthesize pyrethrins; (3) Dehydration into iso Pentadiene can be used to synthesize rubber; (4) This substance can also be used to synthesize high-performance polycarboxylate cement water reducer. [0003] The synthetic method of 3-methyl-3-butene-1-ol mainly contains following three kinds at present: [0004] (1) Using SnCl2 as a catalyst to condense isobutene and formaldehyde to prepare 3-methyl-3-buten-1-ol. GB1197971 uses SnCl2 and ZnCl2 as cat...

AI Technical Summary

Problems solved by technology

This type of method has good application potential, but there are still many shortcomings in the current process: (1) the reaction temperature is as high as 200-300 ° C, the reaction pressure is as high as 10-30 MPa, and the reaction time is longer, generally higher than 30 minutes, In this way, the reactor will be very large in large-scale production, and the equipment investment is very large and dangerous under such harsh conditions; (2) The molar ratio of isobutylene to formaldehyde is generally 10:1 to 20:1. On the one hand, It will cause low effective utilization of equipment, on the other hand, so many isobutene cycles will cause high energy consumption

[0009] 2. The excess of isobutylene is 10-20 times, on the one hand, the volume of the reactor is large, and on the other hand, the energy consumption is increased

[0010] 3. 80% of the reaction system is isobutylene, which is very dangerous

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