82372-77-8Relevant articles and documents
SynThesis, Optical Resolution, and Absoiyte - Pseudotetrahedrai organorheniym complexes (i7-C5H5)Re(NO)(PPh,)(X)
Merrifield, James H.,Strouse, Charles T,Giadysz
, p. 1204 - 1211 (2008/10/08)
Reaction of [(C6H5)Re(NO)(PPh3)(CO)]+BF,r (1) with CH,ONa/CH3OH affords the ester (??C5H6)Re(NO)(PPh3)(COOCH3) (2). Reaction of 2 with (-)-(S)-a-(l-naphthyi)ethyIamine or (+)-(R)-a(l-naphthyl)ethykmine gives amide (^C6H5)Re(NO)(PPh3XCO:NHCH(CH3)C10H7) (8). The diastereomers of 8 are separated by benzene/hexane reerystallization; (-)-(BS)-8 and (+)-(SA)-8 are least soluble. These are treated with CF3C02H and NaBF4 to give (-)-(A)-l and (+)-(S)-l, respectively. Resolved 1 is then used to prepare optically active 2, (i?-C5HB)Re(NO)(PPh3)(CH8) (3), [()7-C5H5)Re(NO}(PPh3)(==H2)]+PF6-(4), (i7-C5H6)Re(NO)(PPhg)(CH2C6H 5) (9), (7j-C5HB)Re(NO){PPh3){CH2CH3) (10), and (7?-C5H5)Re(NO)(PPh3)(CHO) (11) via known procedures. An X-ray crystal structure of (-)-(A)-9 (space group P212121, a = 12.874 (5) A, b = 11.889 (3) A, c = 16.077 (7) K,Z~4,R = 0.034) establishes the absolute configurations of resolved 1-4 and 8-11. Also described are the following: ORD and CD spectra; several unsuccessful resolution attempts; the synthesis of [(jl-C5H5)Re(NO)(PPh3)(CH 2P+Ph2(0-i-menthyl))]+PF6+ (?) (used as an optical purity assay); comparisons with isostructural chiral organometallic complexes.
