4- 3- -2-quinoxalinyl phenol

Quinoxalin-2,3(lH,47i)-dione 58, 2,3-dichloroquinoxalines 59, quinoxalin-2,3(lH,4/i)-dithione 60, 2,3-dibromomettylquinoxalines 61, 4-[3-(4-hydroxyphenyl)-2-quinoxalinyl]phenol(62a),4-[3-(4-mercaptophenyl)-2-quinoxalinyl]thiophenol (62b), 2,3-dipyrrolylquinoxaUnes 63 and 64b, 2,3 dicyanoquinoxaline 65a and its benzo[/]- 65b and the dibenzo[ /i]-65c annulated derivatives as well as 6,7-dicyanoquinoxalines 66 were used among the numerous derivatives of quinoxaline as key compounds for designing of the quinoxaline macrocycles (Chart 2). 

Hydroxyphenyl)-2-quinoxalinyl]phenol (62a) and 4-[3-(4-mercaptophenyl)-2-quinoxalinyl]thiophenol (62b) and their derivatives have been easily prepared from commercially available 4,4 -dimethoxy-benzil 112a,b using a TEBr/HOAc mixture as a demethylating agent... 

When 2-chloroquinoxaliiie is treated with a sodium phenolate (see Section 6.3.2.1.4.5.) in an excess of the corresponding phenol, a mixture of the quinoxalinyl ether and the corresponding benzofuro[2,3- ]quinoxaline is obtained. Quinoxalinyl ethers may be cyclized to benzofuro[2,3-b]quinoxaline using polyphosphoric acid. ... 

Cheung et al. [188] studied 2- 4-[(7-chloro-2-quinoxalinyl)oxy]phenoxy -propanoic acid and its decomposition products (e.g., the etlqrl ester of 2-[4-hydroxyphenoxyjpropanoic acid, 4-[7-chloroquinoxalinyloxy]phenol, 2-hydroxy-7-chloroquinoxaline) were resolved on a C g column (A = 245 ran) using an 80/20/0.1 methanol/water/TFA mobile phase. Elution took 15min. Linear ranges were reported as 80-290 pg/mL with a detection limit of 1.5 ng per injection (S/N = 3). 

The first possibility of assembling our intermediates was to prepare first the 4-[(6-chloro-quinoxalinyl)-oxy]phenol 15 (scheme 12) which was linked with the tosylate 4 in the next step (scheme 13). 

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