Phosphorus oxychloride → N-(4,6-Dichloropyrido[3,2-d]pyrimidin-2-yl)acetamide

Reaction equation

[C:1]([NH:4][C:5]1[N:6]=[CH:7][C:8]2[N:14]=[C:13]([Cl:15])[CH:12]=[CH:11][C:9]=2[N:10]=1)(=[O:3])[CH3:2].C(N(CC)C(C)C)(C)C.O=P(Cl)(Cl)[Cl:27]>O1CCOCC1>[C:1]([NH:4][C:5]1[N:6]=[C:7]([Cl:27])[C:8]2[N:14]=[C:13]([Cl:15])[CH:12]=[CH:11][C:9]=2[N:10]=1)(=[O:3])[CH3:2]

Participants

Procedure

A mixture of 2-acetamido-6-chloro-pyrido[3,2-d]pyrimidine (1.19 g, 5 mmol), N,N-diisopropylethylamine (2.6 ml, 15 mmol) and POCl3 (0.7 ml, 7.5 mmol) in dioxane (50 ml), was stirred at room temperature for 1 hour. After concentration under reduced pressure, the residue was redissolved in dichloromethane (500 ml) and extracted with cold water (200 ml) till pH=6-7. The combined organic layers were dried over MgSO4, filtered and concentrated under reduced pressure to yield the crude title compound which was characterised as follows: MS (m/z): 257, 259 ([M+H]+, 100). This compound was used for further reactions without any purification.