Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement
A novel thermal rearrangement, involving pyrimidine ring opening and subsequent ring closure leading to recyclization of the system, was identified in the reaction of (6-oxo-1,6- dihydropyrimidin-2-yl)guanidines 3 (where NR1R2 = NH2, NH alkyl, NH aralkyl, NHCH2Ph(R)) with triethyl orthoacetate, affo...
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| Format: | Journal Article |
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The Royal Society of Chemistry
2012
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| Online Access: | http://hdl.handle.net/20.500.11937/10305 |
| _version_ | 1848746196111196160 |
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| author | Sachdeva, N. Dolzhenko, Anton Chui, W. |
| author_facet | Sachdeva, N. Dolzhenko, Anton Chui, W. |
| author_sort | Sachdeva, N. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | A novel thermal rearrangement, involving pyrimidine ring opening and subsequent ring closure leading to recyclization of the system, was identified in the reaction of (6-oxo-1,6- dihydropyrimidin-2-yl)guanidines 3 (where NR1R2 = NH2, NH alkyl, NH aralkyl, NHCH2Ph(R)) with triethyl orthoacetate, affording 4-substituted-2-methyl-6H-pyrimido[1,2-a][1,3,5]triazin-6- ones 6 and their ring opened products. However, no such rearrangement was observed with (6- oxo-1,6-dihydropyrimidin-2-yl)guanidines 3 bearing a tertiary amino or anilino substituent (i.e. where NR1R2 = N(CH3)2, indoline, morpholino, NHAr). As expected, 2-substituted-4-methyl- 6H-pyrimido[1,2-a][1,3,5]triazin-6-ones 4 were obtained as the final products. Experimental 2 structural determination and theoretical studies were carried out to get an understanding of the observed thermal rearrangement. In addition, an attempt to obtain similar pyrimido[1,2-a][1,3,5]triazin-6-ones using N,N-dimethylacetamide dimethyl acetal (DMA-DMA) as one carbon inserting synthon had furnished triazine ring annulated product 14 bearing N,N-dimethyl enamino substituent at position 4 as a result of further reaction with a second molecule of DMA-DMA. |
| first_indexed | 2025-11-14T06:29:24Z |
| format | Journal Article |
| id | curtin-20.500.11937-10305 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T06:29:24Z |
| publishDate | 2012 |
| publisher | The Royal Society of Chemistry |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-103052017-09-13T16:06:55Z Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement Sachdeva, N. Dolzhenko, Anton Chui, W. 3 X-ray crystal structure triazines 2-a][1 guanidines pyrimido[1 5]triazines rearrangement pyrimidines A novel thermal rearrangement, involving pyrimidine ring opening and subsequent ring closure leading to recyclization of the system, was identified in the reaction of (6-oxo-1,6- dihydropyrimidin-2-yl)guanidines 3 (where NR1R2 = NH2, NH alkyl, NH aralkyl, NHCH2Ph(R)) with triethyl orthoacetate, affording 4-substituted-2-methyl-6H-pyrimido[1,2-a][1,3,5]triazin-6- ones 6 and their ring opened products. However, no such rearrangement was observed with (6- oxo-1,6-dihydropyrimidin-2-yl)guanidines 3 bearing a tertiary amino or anilino substituent (i.e. where NR1R2 = N(CH3)2, indoline, morpholino, NHAr). As expected, 2-substituted-4-methyl- 6H-pyrimido[1,2-a][1,3,5]triazin-6-ones 4 were obtained as the final products. Experimental 2 structural determination and theoretical studies were carried out to get an understanding of the observed thermal rearrangement. In addition, an attempt to obtain similar pyrimido[1,2-a][1,3,5]triazin-6-ones using N,N-dimethylacetamide dimethyl acetal (DMA-DMA) as one carbon inserting synthon had furnished triazine ring annulated product 14 bearing N,N-dimethyl enamino substituent at position 4 as a result of further reaction with a second molecule of DMA-DMA. 2012 Journal Article http://hdl.handle.net/20.500.11937/10305 10.1039/C2OB25195G The Royal Society of Chemistry fulltext |
| spellingShingle | 3 X-ray crystal structure triazines 2-a][1 guanidines pyrimido[1 5]triazines rearrangement pyrimidines Sachdeva, N. Dolzhenko, Anton Chui, W. Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title | Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title_full | Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title_fullStr | Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title_full_unstemmed | Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title_short | Regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: Observation of an unexpected rearrangement |
| title_sort | regioselective synthesis of pyrimido [1,2-a][1,3,5]triazin-6-ones via reaction of 1-(6-oxo-1,6-dihydropyrimidin-2-yl)guanidines with triethylorthoacetate: observation of an unexpected rearrangement |
| topic | 3 X-ray crystal structure triazines 2-a][1 guanidines pyrimido[1 5]triazines rearrangement pyrimidines |
| url | http://hdl.handle.net/20.500.11937/10305 |