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Haider, N.; Holzer, W., Science of Synthesis, (2004) 16, 257.
Diazotized 2-acylanilines, for example 2-acetylanilines and 2-(haloacetyl)anilines, cyclize smoothly to give cinnolin-4-ols 19 (Scheme 9). This method is known as the Borsche synthesis[84] and represents the most versatile and widely employed route to the latter class of compounds. Many cinnolin-4-ols with a wide variety of substitution patterns have been obtained in this way. At room temperature, the cyclization reaction proceeds slowly, although it can be accelerated either by electron-withdrawing groups meta to the acetyl moiety, or by carrying out the reaction at higher temperatures, but in some cases this results in a lower yield.[85] Examples with R1 = SOMe[86] or SO2X (X = OH, NH2, NHPh, NMe2, Me, Ph)[87] have also been reported. A more recent variation of the Borsche approach is the cyclization of triphenylphosphoranylidene compounds 20 into cinnolin-4-ones 21, which can be subsequently hydrolyzed to give cinnolin-4-ols 22 (Scheme 9).[88]
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M8 | M8 | M8 | M8 | M8 | Meeee (%) | Mee |
---|---|---|---|---|---|---|
Me | M | M | M | M | 88 | [88] |
M | M | Me | M | M | 88 | [88] |
M | M | M | Me | M | 88 | [88] |
8-eeeeeeee | M | M | M | M | 88 | [88] |
Me | M | Me | M | M | 88 | [88] |
M | MMe | M | M | M | 88 | [88] |
M | M | M | MMe | M | 88 | [88] |
M | M | M | M | MMe | 88 | [88] |
M | M | MMe | MMe | M | 88 | [88] |
M | M | MM8 | M | M | 88 | [88,88] |
M | M | M | M | MM8 | 88 | [88,88] |
M | M | MM8 | Me | M | 88 | [88] |
Me | M | MM8 | M | M | 88 | [88] |
M | M | M | M | M | 88 | [88] |
M | M | Me | Me | M | 88 | [88] |
Me | M | Me | M | M | 88 | [88] |
M | M | M | Me | Me | 88 | [88] |
Me | M | Me | Me | M | 88 | [88] |
M | M | Me | Me | M | 88 | [88] |
M | M | M | Me | Me | 88 | [88] |
MMMe | M | M | M | M | 88 | [88] |
MMMe | M | Me | M | M | 88 | [88] |
MMMe | M | Me | M | M | 88 | [88] |
MMMe | M | M | Me | M | 88 | [88] |
MMMe | M | MMe | MMe | M | 88 | [88] |
MM8Me | M | M | M | M | 88 | [88] |
Me | M | M | MMe | M | 88 | [88] |
MM8Me | M | M | M | M | 88 | [88] |
M | M | MMe | M(MM8)8MMe | M | 88 | [88] |
M | M | M | 88 | [88] |
---|---|---|---|---|
MMM8M | M | 88 | [88] | |
M | M | Me | 88 | [88] |
Me | M | M | 88 | [88] |
e Meeeeee eeeee ee 88 eeee 88.
Meeeeeeeeeee Meeeeeeee
8-Meeeeee-8-(8-eeeeeeeeeeeee)eeeeeeee-8-ee [88, M8 = M8 = M8 = M; M8 = MMe; M8 = M(MM8)8MMe]; Meeeeee Meeeeeeee:[88]
M eeee ee MeMM8 (8.8 e, 88 eeee) ee M8M (8 eM) eee eeeee eeeeeeee ee e eeee ee 8-[8-eeeee-8-eeeeeee-8-(8-eeeeeeeeeeeee)eeeeee]eeeeeeee [88, M8 = M8 = M8 = M; M8 = MMe; M8 = M(MM8)8MMe; 88.88 e, 88 eeee] ee MeMM (888 eM) eee M8MM8 (88 eM). Meeee eeeeeeee eee 88 eee ee 88°M, eee eeee eee eeeeeeeeeeee ee eeee ee eee eeeeeeee eeeeee eee eeeeee eeee Me8M (888 eM). Mee eeeee eee eeeeeeeee ee eeeeeeeeee eee eeeeeeeee ee M8M (888 eM). Meeee eee eM eee eeeeeeee ee 8.8 eeee 8 M ee MeMM, eee eeeee eee eeeeeeeee ee eeeeeeeeee eee eeeeee eeee Me8M; eeeee: 8.88 e (88%); ee 888–888°M.
8-Meeeeeeeeeeeee-8-ee (88, M8 = Me; M8 = M8 = M8 = M8 = M); Meeeeee Meeeeeeee:[88]
M eeee ee 8-(8-eeeeeeeeeee)-8-eeeeeeeeeeeeee (88, M8 = Me; M8 = M8 = M8 = M8 = M; 888 ee, 8.88 eeee) ee eeeee MMe (8 eM) eee eeeeeee eeee e eeee ee MeMM8 (88 ee, 8.88 eeee) ee M8M (8 eM) ee 8°M, eee eee eeeeeeeee eeee eeee eee eeee eeeeee ee 88°M eee 8 e. Mee eeeeeeee-8-ee eeeeeee eeeeeeeee ee eeeee eeeeeeee; eeeee: 888 ee (88%); ee 888–888°M. Meeeeeeeeeeee, 888 ee (88%) ee eeeeeee eee eeeeeeee eeee eee eeeeeeeee eeee eeee eee eeee ee ee eee 8 e.
Meeeeeee-8-ee (88, M8 = M8 = M8 = M); Meeeeee Meeeeeeee:[88]
Me e eeee ee eeeeeeeeeeeeeeeeeeeeeeeeee eeeeeeee 88 (M8 = M8 = M8 = M; 8.888 e, 8 eeee) ee MeMM (88 eM) eee 88% ee MMe (8.8 eM), eeeeee eeeeeee (8.88 e, 8.8 eeee) eee eeeee ee 8°M eeee 88 eee. Meeee 88 eee eee eeee eee eeeeeee ee eeee ee ee, eeee eeeeeeee (eM 8–8) eeee 88% ee MeMM, eeeeeee eeee M8M (88 eM), eee eeeeeeeee eeee MMMe8 (8 × 88 eM). Mee eeeeeee eeeee eee eeeee (Me8MM8) eee eeeeeeeeee. Meeee eeeeeeeee ee eee eeeee eeeeeee eeee Me8M, eee eeeeeee eee eeeeeeeee ee eeeeeeeeee eee eeeeeeeeeeeeee (MeMM) ee eeeeee eeeeeeeee 88 (M8 = M8 = M8 = M); eeeee: 8.888 e (88%); ee 888–888°M. M eeee ee 88 (M8 = M8 = M8 = M; 888 ee, 8 eeee) ee MeMM (88 eM) eee 88% ee MeMM (8 eM) eee eeeeeeee eee 8 e. Meeee eeeeeeeeeee ee MeMM, eee eeeeeee eee eeeeeee eeee M8M eee Me8MM eee eeeeeeeee eeee MM8Me8 (8 × 88 eM). Mee eeeeeee eeeee eee eeee eeeeeee eeee 88% ee MMe (8.8 eM) eee eee eeeeeee eee eeeeeeeee ee eeeeeeeeee eee eeeeeeeeeeeeee (MeMM); eeeee: 888 ee (88%); ee 888–888°M.
References
[82] | Meeeee, M. M.; Meeeee, M.; Meeee, M. M.; Meeeeeeee, M., M. Meee. Mee., (8888), 8888. |
[84] | Meeeeee, M.; Meeeeee, M., Meeeee Meeeeee Mee. Meee., (8888) 888, 888. |
[85] | Meeeeeee, M. M.; Meeeeeeee, M., M. Meee. Mee., (8888), 8888. |
[86] | eee Meeeeeeeeee, M.; Meeeeeee, M.; Meeee, M. M.; Meeeee, M., Me., M. Meeeeeeeee. Meee., (8888) 8, 888. |
[87] | Meeeeeee, M., Meeeee Meeeeee Mee. Meee., (8888), 888. |
[88] | Meeeeee, M.; Meeeeeee, M.; Meeeeeee, M.; Meeee, M.; Meeeeee, M., Meeeeeeee, (8888), 888. |
[89] | Meeeeeee, M. M.; Meeeee, M. M., M. Meee. Mee., (8888), 8888. |
[90] | Meeeee, M. M.; Meeeeeeee, M., M. Meee. Mee., (8888), 8888. |
[91] | Meeeee, M. M.; Meeee, M. M., M. Mee. Meee., (8888) 88, 8888. |
[92] | Meeeeeeee, M.; Meeeeee, M. M. M., M. Meee. Mee., (8888), 888. |
[93] | Meeeee, M. M.; Meeeeeeee, M., M. Meee. Mee., (8888), 888. |
[94] | Meeeeee, M. M. M., M. Meee. Mee., (8888), 888. |
[95] | Meeeeeee, M. M.; Meeeee, M. M.; Meeeeee, M. M. M., M. Meee. Mee., (8888), 8888. |
[96] | Meeeeeeee, M.; Meeeeeee, M. M., M. Meee. Mee., (8888), 888. |
[97] | Meeeeeee, M. M.; Meeeeee, M. M. M., M. Meee. Mee., (8888), 888. |
[98] | Meeeeeeee, M.; Meeee, M.; Meeeeeee, M. M., M. Meee. Mee., (8888), 8888. |
[99] | Meeeeeeee, M. M.; Meeeee, M. M.; Meeeeeeee, M.; Meeeee, M. M. M.; Meé, M. M.; Meeeeee, M.-M. M.; Meeeeee, M. M.; Meeee, M.; Meeee, M. M.; Meeeee, M. M.; Meeeeee, M.; Meeeeee-eee eee Meeeee, M., M. Mee. Meee., (8888) 88, 8888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) 8/8, 888.
- 8.Meeeee-Meee, (8888) 88/8, 88.