Compound No.

R

Chemical shift (δ, ppm)

% Yield

3a

Pyrazolo[1,5-a]pyrimidine

7.91

94

3b

2-Methoxyphenol

7.69

92

3c

4-Formylbenzene

8.00

90

3d

4-Fluorobenzene

7.81

85

3e

N,N-Dimethylaminopyrimidine

7.61

81

3f

N-Morpholinepyrimidine

7.64

88

3g

Isopropylpyrimidine

7.62

86