The channels of formation of ester compounds in the liquid-phase oxidation of cyclohexane are reviewed. At least 99.8% cyclohexyl esters of mono- and dicarboxylic acids are formed as a result of cyclohexanol acylation with mixed anhydrides including residues of all compounds with carboxyl groups present in the oxidized cyclohexane. The formation of mixed anhydrides is related to the fast reacylation of adipic anhydride with carboxylic acids. Alcoholysis of mixed anhydrides containing the formic acid residue with cyclohexanol leads mainly to cyclohexyl formate. The formation of ε-caprolactone during cyclohexane oxidation is the result of the Baeyer–Villiger oxidation of cyclohexanone with peroxy acids through α-hydroxy-α-hydroperoxy ester. A decrease in the yield of ε-caprolactone is reached under the conditions of decomposition or reduction of peroxy acids in the presence the compounds of variable valency metals or sulfur-containing reagents, respectively. The cobalt(II) and manganese(II) compounds stimulate the homolytic decomposition of α-hydroxy-α-hydroperoxy ester during which no lactone is formed. The cyclization of 5-hydroxypentanoic acid, which was formed by the oxidative transformations of cyclohexanone, leads to δ-valerolactone. The compounds of variable valency metals slightly affect the yield of δ-valerolactone. The mechanism of ester formation associated with the acylation of oxiranes formed by the radical chain oxidation of carbonyl compounds at the β-CH bonds was proposed.

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环己烷液相氧化生成酯类化合物的机理

综述了环己烷液相氧化中酯类化合物的形成途径。至少99.8%的一元和二元羧酸的环己酯是环己醇与混合酸酐酰化的结果，包括所有具有羧基的化合物的残留物存在于氧化的环己烷中。混合酸酐的形成与己二酸酐与羧酸的快速再酰化有关。含有甲酸残基的混合酸酐与环己醇的醇解主要产生甲酸环己酯。环己烷氧化过程中ε-己内酯的形成是环己酮与过氧酸通过α-羟基-α-氢过氧酯进行Baeyer-Villiger氧化的结果。在分别存在可变价金属化合物或含硫试剂的情况下，在分解或还原过氧酸的条件下达到ε-己内酯产率的降低。钴 (II) 和锰 (II) 化合物会刺激 α-羟基-α-氢过氧酯的均裂分解，在此过程中不会形成内酯。由环己酮氧化转化形成的 5-羟基戊酸环化生成 δ-戊内酯。可变价金属的化合物对δ-戊内酯的产率有轻微影响。提出了与羰基化合物在 β-CH 键处自由基链氧化形成的环氧乙烷酰化相关的酯形成机制。分别。钴 (II) 和锰 (II) 化合物刺激 α-羟基-α-氢过氧酯的均裂分解，在此过程中不会形成内酯。由环己酮氧化转化形成的 5-羟基戊酸环化生成 δ-戊内酯。可变价金属的化合物对δ-戊内酯的产率有轻微影响。提出了与羰基化合物在 β-CH 键处自由基链氧化形成的环氧乙烷酰化相关的酯形成机制。分别。钴 (II) 和锰 (II) 化合物刺激 α-羟基-α-氢过氧酯的均裂分解，在此过程中不会形成内酯。由环己酮氧化转化形成的 5-羟基戊酸环化生成 δ-戊内酯。可变价金属的化合物对δ-戊内酯的产率有轻微影响。提出了与羰基化合物在 β-CH 键处自由基链氧化形成的环氧乙烷酰化相关的酯形成机制。可变价金属的化合物对δ-戊内酯的产率有轻微影响。提出了与羰基化合物在 β-CH 键处自由基链氧化形成的环氧乙烷酰化相关的酯形成机制。可变价金属的化合物对δ-戊内酯的产率有轻微影响。提出了与羰基化合物在 β-CH 键处自由基链氧化形成的环氧乙烷酰化相关的酯形成机制。