2.5- Disubstituted 3-furyl bromide

The reaction of 2,5-disubstituted 3-furyl bromides with butyl-lithium and octafluorocyclopentene in dry tetrahydrofuran (THF) at —78°C gave bis(furyl)ethenes 82 (06JMC4690). Photochrome 83 (05JOC10323, 06EJ03105) (29-46% yield) and a series of its derivatives 84 (55-65%) containing different substituents at position 6 of the ben-zofuran ring were synthesized from 3-bromo-2-methyl-1-benzofuran (08JPP(A)146). 

The reactions of 2,5-disubstituted 3-furyl bromides with butyllithium and OFCP in anhydrous THF at -78° afforded bisfurylethenes 76 [84]. Photochrome 77 [85, 86] (29 6 % yield) and a series of its derivatives 78 (55-65 % yield) with various substituents in position 6 of the benzofuran ring [87] were obtained from 3-bromo-2-methyl-1 -benzofuran. 1,2-Bis(5-n-aIkyl-2-phenyloxazol-4-yl)perfluorocyclopent-enes... 

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