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US 5,206,398 AGranted
Chiral phospholane transition metal catalysts
AssigneeE. I. Du Pont de Nemours and Company
InventorMark J. Burk
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Abstract
Chiral 2,5-disubstituted phospholanes useful as transition metal ligands in asymmetric catalysis and processes for their preparation are disclosed.
Claims8
A complex comprising one or more transition metals, lanthanides or actinides and one or more of the following compounds as ligands ##STR7## wherein:
- R is a lower alkyl, trifluoromethyl, phenyl, substituted phenyl, aralkyl or ring-substituted aralkyl;
- and n is an integer having a value from 1 to 12.
A process for the preparation of a compound of formula I ##STR8## wherein:
- R is a lower alkyl, trifluoromethyl, phenyl, substituted phenyl, aralkyl or ring-substituted aralkyl;
- and
- n is an integer of 1 to 12;
- comprising reacting a phenyl substituted phospholane of formula III ##STR9## wherein R is defined as in formula I, with lithium and a dihalo compound of formula
- X--(CH.sub.2).sub.n --X or R.sup.1 O--(CH.sub.2).sub.n --OR.sup.1
- wherein X is halogen, OR.sup.1 or R.sup.1 O are methanesulfonate, trifluoromethanesulfonate or p-toluenesulfonate, and n is an integer from 1 to 12 to yield the desired compound of formula I.
3 more elements
Dependencies are inferred from the claim text.