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Asymmetric Dearomatization of the Furan Ring Promoted by Conjugate Organolithium Addition to (Menthyloxy)(3‐furyl)carbene Complexes of Chromium
Author(s) -
Barluenga José,
Nandy Sandip K.,
Laxmi Y. R. Santosh,
Suárez José Ramón,
Merino Isabel,
Flórez Josefa,
GarcíaGranda Santiago,
MontejoBernardo José
Publication year - 2003
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200305241
Subject(s) - carbene , chemistry , stereocenter , nucleophile , trifluoromethanesulfonate , regioselectivity , chromium , electrophile , ring (chemistry) , transition metal carbene complex , medicinal chemistry , alkene , furan , stereochemistry , enantioselective synthesis , organic chemistry , catalysis
The sequential low‐temperature addition reaction of an organolithium compound and methyl triflate to (menthyloxy)(3‐furyl)carbene complexes of chromium and tungsten proceeded with excellent regioselectivity (1,4‐addition) and diastereoselectivity (2,3‐ trans disposition of the nucleophile and electrophile groups) to afford new 2,3‐disubstituted (2,3‐dihydro‐3‐furyl)carbene complexes. In addition, a high degree of diastereofacial selectivity was achieved by employing alkenyllithium compounds. After detachment of both the metal fragment and the chiral auxiliary group, trisubstituted 2,3‐dihydrofuran derivatives containing a quaternary stereogenic center at the C3 position were obtained. The characterization, including X‐ray crystallography, of a novel type of stable four‐membered chelate (η 2 ‐alkene)tetracarbonylcarbene complex of chromium is also reported.