ISSN:
0009-2940
Keywords:
Tripod ligand synthesis
;
Oxetane cleavage
;
Phosphane-Boranes
;
Chiral neopentyl system
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Chiral Tripod Ligands: A New Synthetic Route to Chiral C1-symmetrical Neopentyltris(phosphane) Ligands H3CC[CH2P(Ra)2][CH2P(Rb)2][CH2P(Rc)2]A novel synthesis of chiral tripod ligands H3CC[CH2P-(Ra)2][CH2P(Rb)2][CH2P(Rc)2] (6) containing three different donor groups at their neopentyl backbone is described. The key intermediates H3CC[CH2P(Ra)2][CH2P(Rb)2](CH2OH) (3) are easily obtained starting from pentaglycerine, H3CC-(CH2OH)3, via the oxetanes (2) following published procedures. The compounds 3, after protection of the phosphane functions by BH3 {formation of H3CC[CH2P(Ra)2BH3][CH2P(Rb)2BH3](CH20H) (4)} are transformed into the mesylates H3CC[CH2P(Ra)2BH3][CH2P-(RB)2BH3](CH20Ms) (5), which upon reaction with KP(Rc)2 and deprotection with morpholine gives fair yields of racemic 6. The synthetic route described is thus a valuable and efficient alternative to a recently published procedure, based on H3CC(CH2CI)(CH2Br)(CH20S02CF3) as the key intermediate. The compounds 2-6 are obtained in analytically pure form and are fully characterised by spectroscopic data.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19941271004
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