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Please login to access the full content or check if you have access via16.12.1.8.2.1 Reaction of 3-Cyano-2-methylisothiourea or 2-Cyanoguanidines with Ketones
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von Angerer, S., Science of Synthesis Knowledge Updates, (2011) 1, 222.
Cyclization of 3-cyano-2-methylisothiourea 301 (R1 = SMe) with ketones such as pentan-3-one or acetophenone in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene gives 2-(methylsulfanyl)pyrimidin-4-amines, but the yields are low.[465] 2-Cyanoguanidine (301, R1 = NH2) undergoes a similar reaction with various ketones without improvement in the yields.[466] However, when cyclic ketones such as cyclohexanone or cyclopentanone are used, the yields increase considerably and the reaction becomes useful for the synthesis of cyclocondensed pyrimidin-4-amines 302 (Scheme 169).[465,467]
Meeeee 888 Meeeeeeee Meeeeeeee-8-eeeeee eeee Meeeeeeeeeeeee eee 8-Meeee-8-eeeeeeeeeeeeeeeee ee 8-Meeeeeeeeeeeee[888,888]
e | M8 | Meeeeeeeee | Meeee (%) | ee (°M) | Mee |
---|---|---|---|---|---|
8 | MMe | MMM, eeeeee eeee, 888°M, 8 e | 88 | 888–888 | [888] |
8 | MMe | eeeeeeeeeee, eeeeee eeee, 888°M, 8 e | 88 | 888–888 | [888] |
8 | MM8 | 888–888°M, 8.8 e | 88 | 888–888 | [888] |
Meeeeeeeeeee Meeeeeeee
8,8,8,8-Meeeeeeeeeeeeeeeeeeee-8,8-eeeeeee (888, e = 8; M8 = MM8):[888]
M eeeeeee ee 8-eeeeeeeeeeeeee (888, M8 = MM8; 88.8 e, 8.8 eee) eee eeeeeeeeeeeee (88.8 e, 8.8 eee) eee eeeeee ee 888–888°M (eeeeeeee eeeeeeeeeee) ee ee eee eeee ee e eeeee eeeeeeee eeee e eeeee-eeeeee eeeeeeeee, e Meee–Meeee eeeee eeee, eee ee eeeeeeeee eeeeeeeeeee eee 8.8 e. M eeeee eeee eee eeeeeeee eeeee 8 e, eee e eeeee eeeeeee ee eeeeeeeeeee 8 e eeeee. M8M (8.8 eM) eee eeeeeeeee eee eee eeeeeeee eee eeeeeeeeee ee ee eeeeeeee eeee ee eeee M8M eeeeeeeeeee ee eee eeeee eeee. Mee eeeeeee eee eeeeee eee eeeeeeeeee eeee eeeeeee (88 eM), eee eee eeeeeeeee eeeee (88.8 e) eee eeeeeeeee. Meeeeeeeeeeeeee [MMMM (888 eM), 888°M] eeee eee eeeeeee; eeeee: 88.8 e (88%); ee 888–888°M (MeMM).
References
[465] | Meeeee, M.; Meeeeeee, M.; Meeeee, M.; Meee, M.; Meeeee, M., Meee. Meeee. Meee., (8888) 88, 888. |
[466] | Meeeee, M. M.; Meeeeeeeee, M.; Meeeee, M., M. Mee. Meee., (8888) 88, 8888. |
[467] | Meeeee, M. M.; Meeeeeeeee, M.; Meeeeeeee, M. M., M. Mee. Meee., (8888) 88, 8888. |