Ethyl Acrylate → 5,8-Dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidin-2-amine

HRID 279383Notes

Reaction equation

HRID 279383 reaction equation
[NH2:1][C:2]1[N:6]2[C:7](SC)=[N:8][CH:9]=[C:10]([O:11][CH3:12])[C:5]2=[N:4][N:3]=1.[C:15](OCC)(=[O:18])C=C.C[O-].[Na+].COC1C(Cl)=NC(SC)=NC=1.NN.N#CBr>CO>[NH2:1][C:2]1[N:6]=[C:5]2[N:4]([C:7]([O:18][CH3:15])=[N:8][CH:9]=[C:10]2[O:11][CH3:12])[N:3]=1

Participants

8

Reactant 6

HCID 8821Ethyl AcrylateHCID 9321HydrazineHCID 10476Cyanogen BromideHCID 2435114-Chloro-5-methoxy-2-(methylsulfanyl)pyrimidineHCID 10942334Sodium MethoxideHCID 187699643-Amino-8-methoxy-5-methylthio[1,2,4]triazolo[4,3-c]pyrimidine2×

Product 1

HCID 114468885,8-Dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidin-2-amine

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

In U.S. Pat. No. 5,858,924, 2-amino-5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidine is prepared from 3-amino-8-methoxy-5-methylthio[1,2,4]triazolo-[4,3-c]pyrimidine by treatment with ethyl acrylate and sodium methoxide in methanol. The 3-amino-8-methoxy-5-methylthio[1,2,4]triazolo[4,3-c]pyrimidine in turn is prepared from 5-methoxy-4-chloro-2-methylthio-pyrimidine by treatment with hydrazine followed by cyclization with cyanogen bromide. It would be advantageous to produce 2-amino-5,8-dimethoxy[1,2,4]-triazolo[1,5-c]pyrimidine more efficiently and in higher yield. It would also be advantageous to avoid the use of methylthio containing intermediates and the use of ethyl acrylate in the rearrangement of a [1,2,4]triazolo[4,3-c]pyrimidine into a [1,2,4]-triazolo[1,5-c]pyrimidine.

Sources & evidence

ORD record
ord-8947b394203f44999644c474236ba3c6
Source dataset
uspto-grants-2002_03
Patent number
US06362335B1

Reaction notes

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