Synlett 2008(10): 1579-1580  
DOI: 10.1055/s-2008-1072785
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

1,2-Dibromoethane - A Versatile Reagent in Organic Synthesis

Bhaskar Reddy Aluri*
Institut für Biochemie/Anorganische Chemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff Str. 4, 17487 Greifswald, Germany
e-Mail: bhaskarreddyaluri@yahoo.com;
Further Information

Publication History

Publication Date:
07 May 2008 (online)

Introduction

1,2-Dibromoethane (ethylene dibromide) is commonly used as an ‘entrainment reagent’ to chemically activate magnesium in Grignard reagents. It reacts with magnesium to expose a clean, reactive surface capable of converting otherwise unreactive halides into Grignard reagents. [1] It has many advantages over other entrainment agents. It reacts with magnesium to give MgBr2 and ethylene as byproducts and hence does not introduce a second Grignard reagent to the system. 1,2-Dibromoethane is also a useful reagent for activating zinc. [2] [3] This reagent can be used as a source of electrophilic bromine for bromination of carbanions, [4] and also acts as an alkylating agent with many enolates. [5] 1,2-Dibromoethane is a precursor to numerous 1,2-disubstituted ethane derivatives, for example 1,2-ethanedithiol. [6] In addition, it acts as a sacrificial reductant in the conversion of thiocarbonyl compounds to carbonyl compounds, [7] and as an excellent oxidizer in domino carbopalladation-cyclization processes. [8] It was used as a scavenger of lead antiknock agents in gasoline and as a soil fumigant for fumigation of grains and fruits until the early 1980s. It is a useful intermediate in the synthesis of dyes and pharmaceuticals.