Premium
One‐Component Aluminum(heteroscorpionate) Catalysts for the Formation of Cyclic Carbonates from Epoxides and Carbon Dioxide
Author(s) -
Martínez Javier,
CastroOsma José A.,
AlonsoMoreno Carlos,
RodríguezDiéguez Antonio,
North Michael,
Otero Antonio,
LaraSánchez Agustín
Publication year - 2017
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201601370
Subject(s) - chemistry , catalysis , cationic polymerization , bimetallic strip , medicinal chemistry , epoxide , bromide , carbonate , alkyl , benzyl bromide , polymer chemistry , inorganic chemistry , organic chemistry
New neutral and zwitterionic chiral NNO‐donor scorpionate ligands 1 and 2 were designed to obtain new mononuclear and dinuclear NNO‐heteroscorpionate aluminum complexes. Reaction of 1 with [AlR 3 ] (R=Me, Et) in a 1:1 or 1:2 molar ratio afforded the neutral mononuclear alkyl complexes [AlR 2 (κ 2 ‐bpzappe)] {R=Me ( 3 ), Et ( 4 ); bpzappeH=2,2‐bis(3,5‐dimethylpyrazol‐1‐yl)‐1‐[4‐(dimethylamino)phenyl]‐1‐phenylethanol} and bimetallic complexes [{AlR 2 (κ 2 ‐bpzappe)}(μ‐O){AlR 3 }] [R=Me ( 5 ), Et ( 6 )]. By reaction of complexes 3 – 6 with PhCH 2 Br, mononuclear and dinuclear cationic aluminum complexes [AlR 2 (κ 2 ‐bbpzappe)]Br {R=Me ( 7 ), Et ( 8 ); bbpzappeH= N ‐benzyl‐4‐[2,2‐bis(3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl)‐1‐hydroxy‐1‐phenylethyl]‐ N , N ‐dimethylbenzenaminium bromide} and [{AlR 2 (κ 2 ‐bbpzappe)}(μ‐O){AlR 3 }]Br [R=Me ( 9 ), Et ( 10 )] were synthesized. Both neutral aluminum complexes in the presence of Bu 4 NBr and cationic aluminum complexes were investigated as catalysts for cyclic carbonate formation from epoxides and carbon dioxide. Amongst them, complex 10 was found to be an efficient one‐component catalyst for the synthesis of cyclic carbonates from both monosubstituted and internal epoxides and was shown to have broad substrate scope.