Methyl hydrogen hexanedioate

Methyl hydrogen hexanedioate (adipic acid, monomethyl ester) was obtained from Aldrich Chemical Company, Inc. 

METH YLENE-1 -OXO-1,2,3,4-TET-RAHYDRONAPHTHALENE, 88 Methylene transfer, 90 Methyl hydrogen hexanedioate, 1 METHYL 4-HYDROXY-2-BUTYNO-ATE, 81... 

To a 500-mL, round-bottomed flask having a central 34/45 standard taper neck and two 24/40 standard taper necks are added 120 g (0.75 mol) of methyl hydrogen hexanedioate (Note 2), 250 mL of methanol, 4.1 g (0.075 mol) of sodium methoxide, 10 mL of pyridine, and a magnetic stirring bar. The electrode assembly is inserted so that the platinum electrodes are immersed in the solution. A thermometer and reflux water condenser are attached. The mixture is heated to 60°C and stirred until the sodium methoxide dissolves. 

The mixture is electrolyzed with a constant current of 1.1 A (Note 3) until GLC analysis (Note 4) of the solution shows the absence of the peak due to methyl hydrogen hexanedioate. This requires about 23 hr electrolysis is continued for an additional 2.5 hr at the same current (Note 5). Throughout the electrolysis the reaction mixture is maintained at 62-65°C by passage of the current. After about 1 hr of electrolysis, when conditions are stabilized, the reaction may be left unattended. 

Methyl hydrogen hexanedioate Adipic acid, monomethyl ester (8) Hexanedioic acid, monomethyl ester (9) (627-91-8)... 

Sebacic acid (decanedioic) is made on a commercial scale from ricinoleic acid or castor oil (Section 3.3.4). Reaction with sodium hydroxide at 180-270 °C eventually furnishes octan-2-ol and sebacic acid. The reaction probably involves oxidation of secondary alcohol to ketone, double bond migration and retro-aldol cleavage of the 12-oxo-octadec-lO-enoic acid. Sebacic acid has also been made by electrolysis of methyl hydrogen adipate (monomethyl hexanedioate). 

Hexanedioic acid Di-Et ester, in H-10060 Methyl hydrogen azelate, in N-10040... 

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