Table 1.

Study of the Baeyer–Villiger Oxidation of Enones^a

entry	conditions	yield (%)b
1c	mCPBA, CH2Cl2	15
2c	UHP, TFAA, CH2Cl2	decomp.
3c	BTSP, SnCl4, ligand A, 4 Å MS, CH2Cl2	83
4d	BTSP, SnCl4, 4 Å MS, CH2Cl2	trace
5d	BTSP, SnCl4, ligand B, 4 Å MS, CH2Cl2	22
6d	BTSP, SnCl4, pyridine, 4 Å MS, CH2Cl2	32
7d	BTSP, SnCl4, ligand A, CH2Cl2	trace

^aReactions were carried out on 0.25 mmol scale.

^b1H NMR yield.

^cReactions were carried out at 0.1 M concentration with 0.5 equiv of SnCl₄, 0.5 equiv of ligand A, 3.0 equiv of BTSP and 50 mg 4 Å MS at 25 °C.

^dReactions were carried out under the identical conditions in entry 3 with changes indicated in the table.

mCPBA = meta-chloroperoxybenzoic acid, UHP = urea hydrogen peroxide, TFAA = trifluoroacetic anhydride, BTSP = bis(trimethylsilyl)peroxide.