Entry

Conditions

Step 1 t₁ (min)

m-CPBA Equiv

Step 2 t₂ (min)

Yield 4 (%)^a

1

CH₂Cl₂, reflux

300

1.2

120

80

2

CH₂Cl₂, reflux

300

1.2

180

77

3

CH₂Cl₂, reflux

300

1.5

210

87

4

Solvent-free, rt

30

1.5

60

93