1,4-Dibromobenzene → 2-(2,5-Dibromophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

Participants

Role	Name	HCID	Charge
Reactant	1,4-Dibromobenzene	HCID 7804	—
Reagent	Bis(pinacolato)diborane	HCID 2733548	—
Reagent	3-pyridin-2-yl-2-(3-pyridin-2-yl-1H-1,3,2-benzodiazaborol-2-yl)-1H-1,3,2-benzodiazaborole	HCID 122380799	—
Catalyst	Bis(1,5-cyclooctadiene)dimethoxydiiridium	HCID 76001521	—
Solvent	Cyclopentyl methyl ether	HCID 138539	—
Product	2-(2,5-Dibromophenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane	HCID 70700652	62%

Reaction Conditions

Temperature	100 °C

Reaction Steps

The general procedure A was followed using 1,4-dibromobenzene (118.0 mg, 0.5 mmol) and B2pin2 (126.9 mg, 0.5 mmol, 1.0 eq.) as starting material. The resulting mixture was allowed to stir 16 hours at 100 oC. The 1H NMR conversion was 90% and the byproducts were 2,6-di- and 2,5-di- borylated products. The 1H NMR yields of 5ac, 2,6-di- and 2,5-di- borylated products were 67%, 12% and 12% respectively. 5ac was obtained as white solid (112.0 mg, 62%) after purification by silica gel flash chromatography (EtOAc/PE=1:100 v/v). m.p.: 54-56 oC.

Provenance & Evidence

DOI	10.1021/jacs.5b05252
Source dataset	Borylation dataset from Roche
ORD ID	ord-066c508c5a254808b5bb566fd4b02a47
Source note	Borylation dataset from Roche