Conditions optimization for the intermolecular bromoesterification.

Entrya	Bromine source	Frequency	Yield (%)b
1	NBS	20 Hz	0
2	NBS	30 Hz	0
3	DBDMH	20 Hz	74
4	DBDMH	30 Hz	94 (92)c
5d	DBDMH	—	6
6e	DBDMH	—	4
7f	DBDMH	30 Hz	78

^aReactions were conducted using a Retsch mixer mill (MM 400) in a 10 mL zirconium oxide chambers with benzoic acid 7a (0.2 mmol), styrene 8a (0.22 mmol) and bromine source (0.22 mmol) at ambient temperature.

^bDetermined by NMR spectroscopy with dibromomethane as the internal standard.

^cIsolated yield.

^dReaction was conducted in dichloromethane (0.2 M).

^eReaction was conducted under neat condition and the samples were mixed by a magnetic stirrer bar.

^fA planetary mill was used.