CN-117736062-B - Iodine-mediated alcohol reduction method

Abstract

The invention provides an iodine-mediated alcohol reduction method, which relates to the field of organic chemistry; the method uses H 2 as a reducing agent and hydroiodic acid (HI) as a catalyst to catalyze alcohol to deoxidize and reduce, and comprises the following steps of mixing alcohol, HI and a solvent, putting the mixture into a batch reaction kettle, introducing H 2 into the reaction kettle, heating to 100-300 ℃ to react for 1-24H, and carrying out reduction reaction to generate alkane.

Inventors

• PENG YANG
• ZHENG YONGJIE
• ZHANG YUETING
• YANG HAIKUAN
• ZHANG TING
• ZHOU SONGSONG
• FU CHAO
• WU YANFANG
• QIU FENGYING
• WANG XINDONG
• LIU XINLIANG

Assignees

• 江西省林业科学院

Dates

Publication Date

20260508

Application Date

20231219

Claims (5)

1. 1. A method of iodine-mediated alcohol reduction comprising the steps of: Under the action of hydroiodic acid in a hydrogen atmosphere, carrying out reduction reaction on alcohol in a solvent to obtain alkane, wherein the alcohol comprises at least one of benzyl alcohol, linalool, allyl alcohol, benzyl alcohol derivatives and allyl alcohol derivatives, the benzyl alcohol derivatives comprise at least one of 4-methylbenzyl alcohol, 4-isopropylbenzyl alcohol and p-hydroxymethylbenzoic acid, the allyl alcohol derivatives comprise at least one of lactic acid, 2-octenol and 2-hexenol, the concentration of the hydroiodic acid in the reaction is 0.1-10 g/L, and the solvent comprises at least one of acetonitrile, n-hexane, n-heptane, n-octane, cyclohexane and 2-methyltetrahydrofuran.
2. 2. The method according to claim 1, wherein the concentration of alcohol in the reaction is 5-25 g/L.
3. 3. The method of claim 1, wherein the hydrogen gas has a pressure of 0.1 to 5 Mpa.
4. 4. The method according to claim 1, wherein the reaction temperature is 100-300 ℃ and the reaction time is 1-24 h.
5. 5. The method of claim 1, wherein the reaction byproduct is water.

Description

Iodine-mediated alcohol reduction method Technical Field The invention relates to the field of organic chemistry, in particular to an iodine-mediated alcohol reduction method. Background Fossil fuels have been playing a dominant role in the medical, energy and materials industries. Most organic compounds come from fossil fuel primary petrochemical products, typically low-functional hydrocarbons such as benzene, olefins or alkanes. Thus, the focus of research on organic synthesis is on the activation and functionalization of C-H bonds. However, with the exhaustion of fossil fuels, alternative sustainable resources have become an important point of research. Biomass is the only renewable carbon resource that has potential to replace fossil fuels as a feedstock for various chemicals. Due to the nature of its complex functional groups, conversion of biomass to high-value chemicals requires the development of efficient defunctionalization methods, as opposed to petrochemistry. Because biomass contains polyhydroxy functionality, selective deoxygenation of alcohols is an important transformation in biomass chemical synthesis. There are various methods for selective alcohol deoxygenation including free radical deoxygenation, transition metal catalysis, red phosphorus reflux hydroiodic acid deoxygenation. In the free radical deoxygenation reaction, intermediate thioesters are first produced and then reduced by tin reagents. The transition metal catalytic method is a method for catalytic reduction deoxidation of alcohols using a transition metal Ni, co, ir, pd, ru. The red phosphorus reflux hydriodic acid deoxygenation method has been used in industry to date and comprises two steps, a first step in which the hydroxyl groups are converted to the corresponding alkyl iodides which are more easily reduced, and a second step in which the iodides are reduced by excess hydriodic acid to yield alkanes. The method is improved in the following steps that HI catalytic amount, red phosphorus or hypophosphorous acid is used as a reducing agent to reduce iodine simple substance (I 2) into hydroiodic acid (HI), however, phosphorus is oxidized into phosphoric acid, the generated byproducts produce larger pollution to the environment, and the catalyst is not recyclable. At present, the common methods for the alcohol reduction methods of benzyl alcohol, linalool, allyl alcohol, benzyl alcohol derivatives, allyl alcohol derivatives and the like are a free radical deoxidation method and a transition metal catalysis method, however, the problems of more byproducts, serious environmental pollution, expensive catalyst, metal residues and the like exist. There is therefore a need to develop a new solution to ameliorate the above problems. Disclosure of Invention The invention aims to provide an iodine-mediated alcohol reduction method, which comprises the steps of firstly reacting alcohol with a catalyst HI to generate iodinated alkane, and reducing the iodinated alkane with H 2 as a reducing agent at high temperature under the condition of no metal catalysis to generate alkane and HI. The method provided by the invention has the advantages of environmental friendliness, no metal catalysis and strong universality, and simultaneously the method can tolerate benzyl alcohol, allyl alcohol, linalool and derivatives thereof. The invention provides an iodine-mediated alcohol reduction method, which comprises the following steps: Under the action of hydroiodic acid in hydrogen atmosphere, alcohol in the solvent undergoes a reduction reaction to prepare alkane, wherein the alcohol comprises at least one of benzyl alcohol, linalool, allyl alcohol, benzyl alcohol derivatives, linalool derivatives and allyl alcohol derivatives. Alternatively, the derivative is a compound containing a benzyl alcohol or allyl alcohol structure formed by substituting atoms or atomic groups in molecules of the benzyl alcohol or allyl alcohol compound with other atoms or atomic groups, and is called as a derivative of the benzyl alcohol or allyl alcohol. Alternatively, the benzyl alcohol derivatives include 4-methylbenzyl alcohol, 4-isopropylbenzyl alcohol, p-hydroxymethylbenzoic acid. Alternatively, the allyl alcohol derivative comprises lactic acid, 2-octenol, 2-hexenol. Alternatively, the method provided by the invention is divided into two steps of reactions: The first step of reaction, namely reacting alcohol with a catalyst HI to generate iodinated alkane; And the second step of reaction, namely reducing the iodo alkane by taking H 2 as a reducing agent at high temperature under the condition of no metal catalysis to generate alkane and HI. Alternatively, the HI formed in the second reaction step may be used again as a catalyst to participate in the first reaction step. Alternatively, the concentration of alcohol in the reaction is 5-25g/L. Alternatively, the concentration of hydroiodic acid in the reaction is 0.1-10g/L. Optionally, the solvent comprises at least on