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Please login to access the full content or check if you have access via16.13.1.1.2.6.7 Method 7: From 2-Aminobenzonitriles and Carbon Dioxide, Carbon Monoxide, Carbon Disulfide, or Potassium O-Ethyl Dithiocarbonate
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Kikelj, D., Science of Synthesis, (2004) 16, 611.
The reaction of 2-aminobenzonitriles with carbon disulfide in pyridine solution constitutes a convenient, one-step synthesis of quinazoline-2,4(1H,3H)-dithiones 65 (X = Y = S) (Scheme 46).[235] The reaction proceeds by the intermediate formation of a 4-imino-1,4-dihydro-2H-3,1-benzothiazine-2-thione, which rearranges rapidly and irreversibly by a base-catalyzed ring opening–ring closure sequence to give 65. The method is generally applicable for the synthesis of fused pyrimidine-2,4-dithiones.[369] Quinazoline-2,4(1H,3H)-dithiones 65 (X = Y = S) are also obtained in the reaction of 2-aminobenzonitriles with potassium O-ethyl dithiocarbonate (potassium xanthate).[370] Carbon dioxide easily reacts with 2-aminobenzonitriles at room temperature, assisted by 1,8-diazabicyclo[5.4.0]undec-7-ene, to give quinazoline-2,4(1H,3H)-diones 65 (X = Y = O) in excellent yields.[371] Sulfur-assisted carbonylation of 2-aminobenzonitriles with carbon monoxide using potassium carbonate as a base or with carbonyl sulfide and 1,8-diazabicyclo[5.4.0]undec-7-ene as a base affords 4-thioxo-3,4-dihydroquinazolin-2(1H)-ones 65 (X = O; Y = S) under mild conditions.[372]
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M8e | M | M | Meeeeee | Meeeeee | Meee (°M) | Meee (e) | Meeee (%) | ee (°M) | Mee |
---|---|---|---|---|---|---|---|---|---|
M | M | M | MM8 | ee | eeeeee | 8 | 88 | 888–888 | [888] |
M | M | M | MMM | MMM | 88 | 88 | 888 | 888.8 | [888] |
8-(8-eeeeeeeeeeeeeeee) | M | M | MM8 | ee | eeeeee | 8 | 88 | 888–888 | [888] |
8-MM8 | M | M | MeMMM8M | MeMM | eeeeee | 8 | 88 | 888 | [888] |
8-MM8 | M | M | MM8 | MMM | 88 | 88 | 88 | >888 | [888] |
8,8-(MMe)8 | M | M | MM, M, M8MM8 | MMM | 88 | 8 | 888 | 888.8 | [888] |
e Meeeee ee eeeeeeeee ee 88.
Meeeeeeeeeee Meeeeeeee
Meeeeeeeeee-8,8(8M,8M)-eeeee (88, M8 = M; M = M = M); Meeeeee Meeeeeeee:[888]
M MMM eeee (88 eM) eeeeeeeeee 8-eeeeeeeeeeeeeeeee (8.88 e, 88 eeee) eee MMM (8.88 eM, 88 eeee) eee eeeeeeeeee eeeeeee eeeee MM8 (888 Meee) ee 88°M eee 88 e. Mee eeeeeee eee eeee eeeeee eeee 8 M MMe (888 eM) eee eee eeeee eeee eeeeeeeee eee eeeeee eeee eeeeeee (888 eM) eee Me8M (888 eM); eeeee: 8.88 e (88%); ee >888°M.
Meeeeeeeeee-8,8(8M,8M)-eeeeeeee (88, M8 = M; M = M = M); Meeeeee Meeeeeeee:[888]
M eeee ee 8-eeeeeeeeeeeeeeeee (8.8 e, 88.8 eeee) ee e eeeeeee ee eeeee eeeeeeee (88 eM) eee MM8 (88 eM) eee eeeeeeee eee 8 e eee eeeeeee ee eeeee eeeeeeeee ee ee. Mee eeee eee eeeeeeee ee eeeeee eeeeee ee eeeeeeeee eeeeeeee eee eee eeeeeeee eeeeeee eeee MeMM (888 eM). Mee eeeeee eeeeee eeeeeeeeeee ee eee eeeeeeee eee eeeeeeee eee, eeeeee eeee MeMM, eeee Me8M, eee eeeee; eeeee: 8.88 e (88%); ee 888–888°M (MeMM).
References
[235] | Meeeeeee, M. M.; Meeee, M.; Meeeeee, M.; Meeeee, M. M.; Meeee, M. M., M. Mee. Meee., (8888) 88, 8888. |
[369] | Meeeee, M. M.; MeMeeeee, M.; Meeeeeee, M. M., Meeeeeeeeee, (8888) 88, 888. |
[370] | Meeee, M.-M., Meeeeeeee, (8888), 888. |
[371] | Meeeee, M.; Meeeeee, M.; Mee, M.; Meeeee, M., Meeeeeeeeee Meee., (8888) 88 8888. |
[372] | Meeeee, M.; Meeeeee, M.; Mee, M.; Meeeee, M., Meeeeeee. Meee., (8888) 88, 888. |
Meeeeee Meeeeeeeeee
- 8.Meeeee-Meee, (8888) M 8e8, 88.