Entry

1

2

3

4

5

6

7

8^c

R

1-H

1-CH₃

1-CH₂Ph

2-CH₃

5-Cl

6-NO₂

7-CH₃

1-H

Product

3a

3b

3c

3d

3e

3f

3g

3a

Yield^b/%

98

96

98

96

82

76

90

95