Ursula Biermann et.al.: Alkylation of Alkenes: Ethylaluminum
Sesquichloride-Mediated Hydro-Alkyl Additions with Alkyl Chloroformates and Di-
tert-butylpyrocarbonate
- Author(s): Ursula Biermann, Juergen O. Metzger
- Title: Alkylation of Alkenes: Ethylaluminum Sesquichloride-Mediated
Hydro-Alkyl Additions with Alkyl Chloroformates and Di-
tert-butylpyrocarbonate
- Date of Upload: 2004
- Article: Journal of the American Chemical Society (2004), 126(33),
10319-10330, Department of Pure and Applied Chemistry, University of
Oldenburg, Oldenburg, Germany
- Keywords: Alkenes, Alkylations, Carbocations, Chloroformates, Fatty
acids, sustainable development, renewable feedstock, vegetable oil, plant oil
- Abstract:
- A general method for the hydro-alkyl addn. to the nonactivated C:C double
bond of alkenes using alkyl chloroformates (primary, secondary) and di-tert-Bu
pyrocarbonate, mediated by ethylaluminum sesquichloride (Et3Al2Cl3), has been
developed. Reaction of alkyl chloroformates and di-tert-Bu pyrocarbonate,
resp., with Et3Al2Cl3 gives an alkyl cation which is added to the alkene;
hydride transfer to the adduct carbenium ion or, if applicable, 1,2-H shift
followed by hydride transfer from Et3Al2Cl3 to the rearranged adduct carbenium
ion gives the satd. addn. product. The reaction has been applied to 1-alkenes,
2-methyl-1-alkenes, internal double bonds, and to three cyclic alkenes.
Special interest has been focused on alkylations of unsatd. fatty compds.,
such as oleic acid, which are important renewable feedstocks. 2-Methylalkanes,
3-methylalkanes, 2,4-dimethylalkanes, 2,3-dimethylalkanes,
2,2,4-trimethylalkanes, cyclohexylalkanes, and carboxylic acids and esters
with the resp. branched alkyl chain have been synthesized with good to
moderate yields.
- URL: http://www.chemie.uni-oldenburg.de/oc/metzger/publikationen/pdf/104.pdf
(application/pdf)
This shadow-file was created by My Meta Maker
1.6.1. Last Update: Wed Mar 2 11:13:27 2005