A chemoenzymatic process for the preparation of 1,5-dimethyl-2-piperidone (1,5-DMPD) from 2-methylglutaronitrile (MGN) has been demonstrated. MGN was first hydrolyzed to 4-cyanopentanoic acid (4-CPA) ammonium salt using the nitrilase activity of immobilized Acidovorax facilis 72W cells. The hydrolysis reaction produced 4-CPA ammonium salt with greater than 98% regioselectivity at 100% conversion, and at concentrations of 170–210 g 4-CPA/l. Catalyst productivities of at least 1000 g 4-CPA/g dry cell weight (dcw) of immobilized cells were achieved by recycling the immobilized-cell catalyst in consecutive stirred-batch reactions. After recovery of the immobilized cell catalyst for reuse, the 4-CPA ammonium salt in the aqueous product mixture was directly converted to 1,5-DMPD by low-pressure catalytic hydrogenation in the presence of added methylamine.

中文翻译：

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化学酶法生产1,5-二甲基-2-哌啶酮

已经证明了由2-甲基戊二腈（MGN）制备1,5-二甲基-2-哌啶酮（1,5-DMPD）的化学酶法。首先利用固定化的Acidovorax facilis的腈水解酶活性将MGN水解为4-氰基戊酸（4-CPA）铵盐。72W电池。水解反应产生4-CPA铵盐，在100％转化率下，浓度为170-210 g 4-CPA / l，其区域选择性大于98％。通过在连续的搅拌分批反应中回收固定化的细胞催化剂，可实现至少1000 g 4-CPA / g固定化细胞的干细胞重量（dcw）的催化剂生产率。回收固定化的细胞催化剂以供再使用后，在添加的甲胺的存在下，通过低压催化氢化将含水产物混合物中的4-CPA铵盐直接转化为1,5-DMPD。