Synthesis and X-ray Structure of Metalated Rhodium(II) Catalysts with a Chiral Phospholane

• Published in: European journal of inorganic chemistry Vol. 2001; no. 1; pp. 105 - 109
• Main Authors: Estevan, Francisco, Krueger, Peter, Lahuerta, Pascual, Moreno, Eduardo, Pérez-Prieto, Julia, Sanaú, Mercedes, Werner, Helmut
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag GmbH 01-01-2001; WILEY‐VCH Verlag GmbH
• Subjects: Carbocycles; Chirality; Diazo compounds; P ligands; Rhodium
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/1099-0682(20011)2001:1<105::AID-EJIC105>3.0.CO;2-Y

The reaction of Rh2(O2CR)4 (R = CH3, CF3) with the chiral phosphane (2S,5S)‐2,5‐dimethyl‐1‐phenylphospholane (PC*H), results in the formation of two diastereoisomers of Rh2(O2CCR)2(PC*)2, with (P) and (M) configuration. These can easily be isolated by chromatographic methods to obtain enantiomerically pure RhII compounds. Preliminary catalytic studies have shown that they induce moderate asymmetry in the cyclization of 5‐aryl‐1‐diazo‐2‐pentanones and 1‐diazo‐5‐hexen‐2‐one. X‐ray analysis of the (M) diastereoisomer with formula Rh2(O2CCCH3)2(PC*)2 is reported. The crystallographic parameters are as follows: space group P21212 (orthorhombic) with a = 12.1347(11) Å, b = 14.5870(13) Å, c = 9.8171(9) Å.