Encyclopedia of Reagents for Organic Synthesis
Copyright © 2001 John Wiley & Sons, Ltd
Article Online Posting Date: April 15, 2001
C8H16BBrO2 (MW 234.93)
InChI = 1/C8H16BBrO2/c1-7(2)11-9(5-6-10)12-8(3)4/h5-8H,1-4H3/b6-5+
InChIKey = OCOSAJWMDGEJAM-AATRIKPKBQ
((E)-vinylation reagent, useful for synthesis of (E)-alkenes, ,-unsaturated ketones, and ,-unsaturated esters)
Physical Data: bp 73 °C/12 mmHg.
Solubility: sol ether, THF, CH2Cl2, and CHCl3.
Form Supplied in: colorless liquid; not available commercially.
Analysis of Reagent Purity: purity is analyzed by 1H NMR (CDCl3): 1.17 (d, J = 6 Hz, 12H), 4.224.56 (m, 2H), 6.37 (d, J = 15 Hz, 1H), 7.06 (d, J = 15 Hz, 1H).
Preparative Methods: by the bromoboration of acetylene with tribromoborane,2 followed by the addition of isopropanol to the resulting 2-(bromovinyl)dibromoborane (eq 1).3, 4 The reagent is isolated by distillation under nitrogen. Large quantities may be prepared and stored in a refrigerator.
Handling, Storage, and Precautions: moisture sensitive; can be handled in air for a short time but is gradually hydrolyzed to the boronic acid by moisture. It
should be stored in a refrigerator under a dry inert gas and transferred by syringe. After prolonged storage it should be
distilled under a dry inert gas before use. Sensitive to both base and acid; base treatment causes rapid decomposition by