Study On The One-pot Reaction From Alcohols To Amides

Amide compounds are compounds whose hydrogen of amino is replaced by acyl, and amide linkage(-CONH-, also called peptide bond) is contained. Amide bond has the characteristics of conformational diversity, structure stability, and is an important structural unit in biological protein and pharmaceutical chemistry. At present, the amide compounds are widely used in chemical raw materials, pharmaceutical synthesis, fuel, and other fields, then synthesis of amide compounds has also increasingly become a research hotspot in the field of organic chemistry.In this paper, two methods of green, low toxicity were used to synthesize amide compounds; the influence of reaction temperature, reaction time, oxidant, the ratio of material conditions is exploried to research, and then a good synthetic conditions was found out.The first method: When alcohols were choosed as the substrate, ammonia water as source of nitrogen and alkaline reagent, 30%H2O2 as oxidant, I2 as catalyst, under the condition of the water a system of one-pot synthesis was carried to obtain amide compounds. The reaction included two steps: the first step was to mix alcohol with intermediate nitrile, the second step was to oxidatize nitrile into generated amide.Benzyl alcohol and hexyl alcohol were taken as substrates; the change law of raw material, intermediate product and product was detected by GCMS. After screening various conditions, the synthetic conditions were determined. 1. When benzene alcohols was choosed as the substrate to synthesize amide, reaction temperature 65 ℃, the reaction time 2 h, alcohol and I2 material ratio 1:3, oxidant 30% H2O2, oxidant dosage 10 m L, reaction system p H 13 were choosed as the good conditions, conversion of benzyl alcohol was 99%, the yield was 87%. 2. When hexyl alcohol was choosed as the substrate to synthesize amide, reaction temperature 65 ℃, reaction time 5 h, alcohol and I2 material ratio 1:3, oxidant 30%H2O2, the dosage of oxidant 10 m L, reaction system p H 12 were choosed the good condition, conversion of hexyl alcohol was 78%, the yield was 54%.The second method: When benzene alcohols was choosed as the substrate, organic amine as nitrogen source, strong alkali weak acid salt as alkaline reagents, Ias catalyst, TBHP as an oxidant of one-pot synthesis was carried to obtain amide compounds. Alcohol was first oxidized to generate aldehyde by TBHP, aldehyde and amine under the action of TBHP was oxidized to generate amide in the method.Benzyl alcohol was taken as the substrate; the changing rule of raw materials, intermediate products and product was detected by GCMS. After screening of various conditions, n-Butylamine hydrochloride, solvent H2 O, alkaline reagent Ba CO3, dosage of alkaline reagent 2 equiv, the dosage of oxidant TBHP 5 equiv were choosed as the good reaction conditions of benzyl alcohol as the substrate to synthesize amide, coversion of benzyl alcohol was 100%, the yield of the amide was 93%. A method was established that the water was choosed as the solvent, Na I/Fe3+ as catalyst, organic amine hydrochloride as nitrogen source, in the absence of inert gas to synthesize amides of high yield in this paper.