Acetylenedicarboxyuc Acid

The reverse reaction (that is, the oxidation of a vinyl radical by Fe to the corresponding vinyl cation) may be involved in the reaction of the dimethyl ester of acetylenedicarboxyUc acid 261 with Fenton s reagent [Fe —H2O2, (217)] (216). When 261 was treated with Fe —H2O2 and the reaction mixture was extracted with ether, a small amount of furan 262 was isolated. A possible mechanism (216) for its formation may be addition of hydroxyl radical to the triple bond of 261, followed by addition of the intermediate vinyl radical to a second molecule of 261 and oxidation of the resulting radical with Fe to the corresponding vinyl cation, followed by cyclization to 262, as shown in Scheme XX. 

Acetylene, purification, 39, 58 Acetylene, diphenyl-, 34, 42 y-hydroxypropyl, 33, 68 Acetylenedicarboxyuc acid, dimethyl ESTER, 32, SS Acetylenic glycols, 39, 57 2- -Acetylphenylhydroquinone, 34,1 S-Acetyl- -valeric acid, 31, 3 Acid chlorides, 39, 19 synthesis of, 37, 69... 

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