skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Triketiminate bis(borohydride) complexes of rare-earth metals [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y, Nd): synthesis, structure, and catalytic activity in polymerization of rac-lactide, ε-caprolactone, and isoprene

Abstract

A new triketimine (2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}CH(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t}) (1) was synthesized by the reaction of imidoyl chloride 2,6-Me{sub 2}C{sub 6}H{sub 3}N=CClBu{sup t} with lithium diketiminate (2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}CHLi. In the crystalline state, compound 1 exists in the diimineenamine form; in solution, in the triimine form. The metalation of triketimine 1 with n-butyllithium in THF at 0 °C produced lithium triketiminate [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Li(THF){sub 2} (2). The metathesis reactions of Ln(BH{sub 4}){sub 3}(THF){sub 3} (Ln = Y, Nd) with compound 2 (1: 1 molar ratio, THF) gave the neutral triketiminate bis(borohydride) complexes [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y (3), Nd (4)). As opposed to the complexes with neutral triketimine, the monoanionic triketiminate ligand is coordinated to Li and Y or Nd cations in a bidentate fashion. Complexes 3 and 4 catalyze the polymerization of rac-lactide and ε-caprolactone; in combination with [Ph{sub 3}C][B(C{sub 6}F{sub 5}){sub 4}] and AlBu{sub 3}{sup i} (1 : 1 : 10 molar ratio), these compounds exhibit catalytic activity in the polymerization of isoprene.

Authors:
;
Publication Date:
OSTI Identifier:
22863510
Resource Type:
Journal Article
Journal Name:
Russian Chemical Bulletin
Additional Journal Information:
Journal Volume: 66; Journal Issue: 9; Other Information: Copyright (c) 2017 Springer Science+Business Media, LLC, part of Springer Nature; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1066-5285
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BOROHYDRIDES; CATALYSIS; CATIONS; CHLORIDES; COMPLEXES; CRYSTALS; ISOPRENE; LIGANDS; LITHIUM; POLYMERIZATION; RARE EARTHS; SOLUTIONS; SYNTHESIS; TETRAHYDROFURAN

Citation Formats

Skvortsov, G. G., Cherkasov, A. V., and Trifonov, A. A., E-mail: trif@iomc.ras.ru. Triketiminate bis(borohydride) complexes of rare-earth metals [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y, Nd): synthesis, structure, and catalytic activity in polymerization of rac-lactide, ε-caprolactone, and isoprene. United States: N. p., 2017. Web. doi:10.1007/S11172-017-1939-9.
Skvortsov, G. G., Cherkasov, A. V., & Trifonov, A. A., E-mail: trif@iomc.ras.ru. Triketiminate bis(borohydride) complexes of rare-earth metals [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y, Nd): synthesis, structure, and catalytic activity in polymerization of rac-lactide, ε-caprolactone, and isoprene. United States. https://doi.org/10.1007/S11172-017-1939-9
Skvortsov, G. G., Cherkasov, A. V., and Trifonov, A. A., E-mail: trif@iomc.ras.ru. 2017. "Triketiminate bis(borohydride) complexes of rare-earth metals [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y, Nd): synthesis, structure, and catalytic activity in polymerization of rac-lactide, ε-caprolactone, and isoprene". United States. https://doi.org/10.1007/S11172-017-1939-9.
@article{osti_22863510,
title = {Triketiminate bis(borohydride) complexes of rare-earth metals [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y, Nd): synthesis, structure, and catalytic activity in polymerization of rac-lactide, ε-caprolactone, and isoprene},
author = {Skvortsov, G. G. and Cherkasov, A. V. and Trifonov, A. A., E-mail: trif@iomc.ras.ru},
abstractNote = {A new triketimine (2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}CH(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t}) (1) was synthesized by the reaction of imidoyl chloride 2,6-Me{sub 2}C{sub 6}H{sub 3}N=CClBu{sup t} with lithium diketiminate (2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}CHLi. In the crystalline state, compound 1 exists in the diimineenamine form; in solution, in the triimine form. The metalation of triketimine 1 with n-butyllithium in THF at 0 °C produced lithium triketiminate [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Li(THF){sub 2} (2). The metathesis reactions of Ln(BH{sub 4}){sub 3}(THF){sub 3} (Ln = Y, Nd) with compound 2 (1: 1 molar ratio, THF) gave the neutral triketiminate bis(borohydride) complexes [(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CMe){sub 2}C(2,6-Me{sub 2}C{sub 6}H{sub 3}N=CBu{sup t})]Ln(BH{sub 4}){sub 2}(THF){sub 2} (Ln = Y (3), Nd (4)). As opposed to the complexes with neutral triketimine, the monoanionic triketiminate ligand is coordinated to Li and Y or Nd cations in a bidentate fashion. Complexes 3 and 4 catalyze the polymerization of rac-lactide and ε-caprolactone; in combination with [Ph{sub 3}C][B(C{sub 6}F{sub 5}){sub 4}] and AlBu{sub 3}{sup i} (1 : 1 : 10 molar ratio), these compounds exhibit catalytic activity in the polymerization of isoprene.},
doi = {10.1007/S11172-017-1939-9},
url = {https://www.osti.gov/biblio/22863510}, journal = {Russian Chemical Bulletin},
issn = {1066-5285},
number = 9,
volume = 66,
place = {United States},
year = {Fri Sep 15 00:00:00 EDT 2017},
month = {Fri Sep 15 00:00:00 EDT 2017}
}