5- Amino-4-chloro-6- pyrimidines

These factors are sufficient to produce similar amounts of aminated isomers from 2,4-dichloropyrimidine which gives predominantly 4-alkoxylation products. Thus, a mixture of 2-amino-4-chloro- (302) and 4-amino-2-chloro-pyrimidine (303) is obtained on treatment of 2,4-dichloropyrimidine with alcoholic ammonia (25°, <18 hr), the reagent here being better at hydrogen bonding than piperidine. 

In crystals of organic compounds, a type of disorder sometimes occurs which is akin to the mixed crystal type for instance, in the crystal of 2-amino-4-methyl-6-chloro-pyrimidine... 

A series of carbocyclic analogues of puromycin have been prepared, e.g. (13), derived from stereoisomers of l-amino-3-azido-2,4,5-trihydroxycyclo-pentane and 4-chloro-pyrimidine precursors, and similarly carbocyclic analogues of uridine and thymidine were made from 1-amino tetrahydroxy-cyclopentanes and nitrourea. A number of 9-(3-amino-2,4-dihydroxycyclo-pentyl)-adenine derivatives have been obtained from a bicyclic cyclopentene... 

Amino- from 4,6-dichloro- via 4-amino-6-chloro-pyrimidines... 

Tetrazolo[l,5-c]pyrimidine, 8-amino-7-chloro-purine synthesis from, 5, 591 Tetrazolopyrimidines... 

Thieno[2,3-d]pyrimidine, 4-amino-synthesis, 4, 1017, 1018 Thieno[2,3-d]pyrimidine, 4-chloro-synthesis, 4, 1017... 

Thiocyanato groups in pyrimidines (138 where R2 is chloro or amino) have been replaced with amines, ethoxide ion, phenoxide ion, and thiourea. 

The deactivating effects of 2- and -amino groups in pyrimidine provide an interesting comparison. The 2-ethyleneimino group deactivates the 4- and 6-chlorines in 183 toward ethyleneimine in benzene at 50°, while the 4-ethyleneimino group in 184 deactivates the 6- but not the 2-chloro group. However, in contrast, 2-amino-... 

The catalytic effect of protons, of bifunctional catalysts, and of base is demonstrated in the amination of chloro derivatives of pyridazine, pyrimidine, and s-triazine (Tables V and VI). Anilino-s-triazines containing NH groups act as catalysts in their own formation. The catalytic action of protons on anhino-dechlorination of 2-chloro-4,6-diamino-s-triazine and of 2-amino-4-chloropyrimidine was reported in the classic paper by Banks. ... 

Chloropyrimidine is aminated with alcoholic ammonia at 130° while 4-chloro-2-methyl- and 4-chloro-6-methyl-pyrimidine yield the corresponding 4-amino derivatives at 100°. 4-Aminopyrimi-dine is not prepared from the chloro analog because of facile self-quatemization (see Section III, B, 2 for comments on factors involved) of the latter. 

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