2,4-Diamino-5-[3,4-dimethoxy-5-(1-methyl-2-propynyloxy)benzyl]pyrimidine → 2,4-diamino-5-(7,8-dimethoxy-2-methyl-2H-1-benzopyran-5-ylmethyl)pyrimidine
Reaction equation
[NH2:1][C:2]1[N:7]=[C:6]([NH2:8])[C:5]([CH2:9][C:10]2[CH:15]=[C:14]([O:16][CH:17]([CH3:20])[C:18]#[CH:19])[C:13]([O:21][CH3:22])=[C:12]([O:23][CH3:24])[CH:11]=2)=[CH:4][N:3]=1>C(N(CC)C1C=CC=CC=1)C>[NH2:1][C:2]1[N:7]=[C:6]([NH2:8])[C:5]([CH2:9][C:10]2[C:15]3[CH:19]=[CH:18][CH:17]([CH3:20])[O:16][C:14]=3[C:13]([O:21][CH3:22])=[C:12]([O:23][CH3:24])[CH:11]=2)=[CH:4][N:3]=1Participants
3
Procedure
A solution of 2,4-diamino-5-[3,4-dimethoxy-5-(1-methyl-2-propynyloxy)-benzyl]pyrimidine (4.28 g, 13.0 mmol) in N,N-diethylaniline (200 mL) was refluxed under nitrogen for 0.5 hr. The hot solution was filtered to remove dark tarry material. The filtrate was cooled and diluted with hexanes (200 mL). The precipitate (3.8 g) was recrystallized from ethanol to give title compound as off-white powder (1.56 g, 37%); mp 219°-221° dec. Anal. Calcd for C17H20N4O3 : C, 62.18; H, 6.14; N, 17.06. Found: C, 61.91; H, 6.20; N, 16.93.