2-Furyl acetonitrile derivatives

Efficient synthesis of 2-chlorofuran is best achieved by decarboxylation of 2-chlorofuran-5-carboxylic acid (63JGU1397) or via the lithium derivative of furan. When furan or 3-bromofuran were treated in turn with ethyl-lithium and hexachloroethane, 2-chlorofuran (48%) or 3-chlorofuran (54%) was formed, uncontaminated by any polychlorinated products (73SC213). Chlorodesilylation of ethyl 5-trimethylsilyl-2-furoate with sul-furyl chloride in acetonitrile gave the 5-chloro ester in —85% yield (91MI4). 

In an analogous way furfuryl alcohol and l-(2-furyl) ethanol are converted to 6-hydroxy-2H-pyran-3 (6H)-one and its 2-methyl derivative, respectively, upon treatment with hydrogen peroxide in acetonitrile in the presence of TS-1. Here dicarbonyl formation is followed by cyclization towards a stable hemiacetal [74],... 

---