Detail of "3903-40-0"

Reference

Dimethyl hexadecanedioate electrochemical production

Dimethyl hexadecanedioate electrochemical production. (Asahi Chemical Industry Co., Ltd., Japan). Jpn. Kokai Tokkyo Koho JP 58161784 A2 26 Sep 1983 Showa, 6 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C25B003-10. APPLICATION: JP 82-40711 17 Mar 1982. DOCUMENT TYPE: Patent CA Section: 72 (Electrochemistry) Section cross-reference(s): 23 Di-Me hexadecanedioate (I) [19102-90-0] is prepd. by the Kolbe reaction in a modified manner: a mixt. of mono-Me dodecanedioate (II) [3903-40-0] and mono-Me adipate (III) [627-91-8] (mol. ratio = 1:(0.5-2)) is dissolved in MeOH contg. their metal salts, and anodically treated with circulation until the concn. of II is lowered preferably to 2-4% of the soln., and then addnl. III is added. The method enables one to smoothly carry out the Kolbe reaction between II and III which, by conventional method, produces a polymeric layer on the anode surface that increases the voltage drop and arrests the passage of current. Thus, a MeOH soln. 1 kg contg. III 9.84, II 15, III as the K salt 1.35, II as the K salt 1.93, and H2O 3 wt.% was circulated through an electrolytic cell equipped with a Ti cathode and a Pt-plated Ti anode (1 ′ 100 cm). The flow rate, c.d., and temp. 22399-98-0 and 19102-90-0 are cas registry numbers of chemicals which are used as reagents here. were 2 m/s, 11 A/dm2, and 48-52°, resp. During electrolysis, III and II were continuously added to the soln. over a 5-h period at the rate of 23 and 36.8 g/h, resp. The concns. of the components were measured, and when III and II reached 0.52 and 2.6%, resp., III 150 g was added. After 12 h, the concns. reached 0.03%. The product concns. were I 14.6, di-Me docosanedioate [22399-98-0] 7.59, and di-Me sebacate [106-79-6] 11.7 wt.%. .