Achiral and chiral PNP-pincer ligands with a carbazole backbone

• Verfasst von: Grüger, Nora [VerfasserIn]
• Verfasst von: Rodríguez Broncano, Lara-Isabel [VerfasserIn]
• Verfasst von: Wadepohl, Hubert [VerfasserIn]
• Verfasst von: Gade, Lutz H. [VerfasserIn]
• Titel: Achiral and chiral PNP-pincer ligands with a carbazole backbone
• Titelzusatz: coordination chemistry with d8 transition metals
• Verf.angabe: Nora Grüger, Lara-Isabel Rodríguez, Hubert Wadepohl, and Lutz H. Gade
• E-Jahr: 2013
• Jahr: January 30, 2013
• Umfang: 10 S.
• Fussnoten: bei "d8" ist die "8" hochgestellt ; Gesehen am 17.02.2021
• Titel Quelle: Enthalten in: Inorganic chemistry
• Ort Quelle: Washington, DC : American Chemical Society, 1962
• Jahr Quelle: 2013
• Band/Heft Quelle: 52(2013), 4, Seite 2050-2059
• ISSN Quelle: 1520-510X
• DOI: doi:10.1021/ic302454n
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1745986723

Abstract

Two new monoanionic PNP pincer type ligands have been synthesized, the achiral 3,6-di-tert-butyl-1,8-bis((diphenyl-phosphino)methyl)-9H-carbazole CbzdiphosH (5) and the chiral 3,6-di-tert-butyl-1,8-bis(((2R,5R)-2,5-diphenylphospholan-1-yl)methyl)-9H-carbazole CbzdipholH (7), both of which were initially prepared as their borane complexes. The synthesis of CbzdiphosH is based on the reaction between the key intermediate 1,8-bis(bromomethyl)-3,6-di-tert-butyl-9H-carbazole (3) and lithium diphenylphosphide-borane complex. The chiral ligand CbzdipholH was prepared by treating 3 with lithium (2R,5R)-2,5-diphenylphospholanide-borane complex and subsequent deprotection with diethylamine. The complexation of the two ligands with nickel, palladium and rhodium was investigated, for which the conformational behavior of the ligands was found to be different. Although the arrangement of the donor atoms in all crystallographically characterized complexes is approximately square planar, the carbazole plane in Cbzdiphos complexes is inclined relative to the coordination plane. On the other hand, a helical twist is observed in Cbzdiphol complexes.