Synthesis of the two minor isomers, delta- and epsilon-1,2,5,6,9,10-hexabromocyclododecane, present in commercial hexabromocyclododecane.
Hexabromocyclododecane (HBCD) is prepared commercially by bromination of cis,trans,trans-cyclododecatriene (ctt-CDT) and widely used as a flame retardant, particularly in polystyrene foams. Commercial HBCD consists largely of three diastereomers, alpha-, beta-, and gamma-HBCD, the structures of which have been known for many years. Recently, the presence in the mixture of small amounts of two minor diastereomers, delta- and epsilon-HBCD, has been reported. Bearing in mind the manner in which commercial HBCD is generated, it was anticipated that these components are probably formed by bromination of trans,trans,trans-cyclododecatriene (ttt-CDT), a common contaminant in commercial ctt-CDT. Indeed, when a sample of ttt-CDT was brominated it gave two products, the NMR spectra and LC/MS and GC/MS behaviour of which confirmed that they are identical to the minor components, delta- and epsilon-HBCD, present in commercial HBCD.
Arsenault
Gilles
G
Wellington Laboratories Inc., Research Division, 345 Southgate Drive, Guelph, Ont., Canada N1G 3M5. gilles@well-labs.com
Konstantinov
Alexandre
A
Marvin
Chris H
CH
MacInnis
Gordia
G
McAlees
Alan
A
McCrindle
Robert
R
Riddell
Nicole
N
Tomy
Gregg T
GT
Yeo
Brian
B
D002853:Chromatography, Liquid; D005411:Flame Retardants / Q000138:chemical synthesis; D008401:Gas Chromatography-Mass Spectrometry; D006842:Hydrocarbons, Brominated / Q000138:chemical synthesis* / Q000737:chemistry*; D013058:Mass Spectrometry; D015394:Molecular Structure; D013237:Stereoisomerism
D005411:Flame Retardants; D006842:Hydrocarbons, Brominated; C089796:hexabromocyclododecane