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

Title: Synthesis and Reactivity of Palladium(II) Alkyl Complexes that Contain Phosphine-cyclopentanesulfonate Ligands

Abstract

The synthesis of the phosphine-cyclopentanesulfonate pro-ligands Li/K[2-PPh 2-cyclopentanesulfonate] (Li/K[2a]), Li/K[2-P(2-OMe-Ph) 2-cyclopentanesulfonate] (Li/K[2b]), and H[2b], and the corresponding Pd(II) alkyl complexes (κ 2- P, O-2a)PdMe(pyridine) (3a) and (κ 2- P, O-2b)PdMe(pyridine) (3b) is described herein. The sulfonate-bridged base-free dimer {(2b)PdMe} 2 (4b) was synthesized by abstraction of pyridine from 3b using B(C 6F 5) 3. The borane-coordinated base-free dimer [{2b·B(C 6F 5) 3}PdMe] 2 (5b), in which B(C 6F 5) 3 binds to a sulfonate oxygen, was prepared by addition of 1 equiv of B(C 6F 5) 3 per Pd to 4b or addition of 2 equiv of B(C 6F 5) 3 to 3b. Compounds 3b, 4b, and 5b polymerize ethylene with low activity (up to 210 kg mol –1 h –1 at 250 psi and 80 °C) to linear polyethylene ( M n = 1950–5250 Da) with predominantly internal olefin placements. 3b and 4b copolymerize ethylene with methyl acrylate to linear copolymers that contain up to 11.7 mol % methyl acrylate, which is incorporated as –CH 2CH(CO 2Me)CH 2– (80%) in-chain units and –CH 2CH(CO 2Me)Me (8%) and –CH 2CH=CH(CO 2Me) (12%) chain-end units. 3b and 4b also copolymerize ethylene with vinyl fluoride to linear copolymers that contain up tomore » 0.41 mol % vinyl fluoride, which is incorporated as –CH 2CHFCH 2– (~80%) in-chain units and –CH 2CF 2H (7%), –CH 2CHFCH 3 (5%), and –CH 2CH 2F (8%) chain-end units. Complexes 3b and 4b are more stable and active in ethylene polymerization than analogous (PAr 2- CH 2 CH 2SO 3)PdR catalysts, but are less active than analogous (PAr 2- arenesulfonate)PdR catalysts. Low-temperature NMR studies show that 4b reacts with ethylene below -10 °C to form the ethylene adduct cis- P, R-(2b)PdMe(ethylene) (7b), which undergoes ethylene insertion at 5 °C. DFT calculations for a model (PMe 2-cyclopentanesulfonate)Pd(Pr)(ethylene) species show that ethylene insertion proceeds by cis- P, R/ trans- P, R isomerization followed by migratory insertion, and that the lower activity of 3b and 4b vis-à-vis analogous (PAr 2-arenesulfonate)PdR catalysts results from a higher barrier for migratory insertion of the trans- P, R isomer.« less

Authors:
 [1]; ORCiD logo [1]
  1. Univ. of Chicago, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Science Foundation (NSF); US Department of Education; USDOE Office of Science (SC)
OSTI Identifier:
1399121
Grant/Contract Number:  
CHE-0911180; CHE-1709159; CHE-1048528; P200A120093; ACI-1548562; AC02-06CH11357; NSF/CHE-1346572
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Organometallics
Additional Journal Information:
Journal Volume: 36; Journal Issue: 17; Journal ID: ISSN 0276-7333
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Palladium; Hydrocarbons; Copolymerization; Catalysts; Molecular structure

Citation Formats

Black, Rebecca E., and Jordan, Richard F. Synthesis and Reactivity of Palladium(II) Alkyl Complexes that Contain Phosphine-cyclopentanesulfonate Ligands. United States: N. p., 2017. Web. doi:10.1021/acs.organomet.7b00572.
Black, Rebecca E., & Jordan, Richard F. Synthesis and Reactivity of Palladium(II) Alkyl Complexes that Contain Phosphine-cyclopentanesulfonate Ligands. United States. doi:10.1021/acs.organomet.7b00572.
Black, Rebecca E., and Jordan, Richard F. Wed . "Synthesis and Reactivity of Palladium(II) Alkyl Complexes that Contain Phosphine-cyclopentanesulfonate Ligands". United States. doi:10.1021/acs.organomet.7b00572. https://www.osti.gov/servlets/purl/1399121.
@article{osti_1399121,
title = {Synthesis and Reactivity of Palladium(II) Alkyl Complexes that Contain Phosphine-cyclopentanesulfonate Ligands},
author = {Black, Rebecca E. and Jordan, Richard F.},
abstractNote = {The synthesis of the phosphine-cyclopentanesulfonate pro-ligands Li/K[2-PPh2-cyclopentanesulfonate] (Li/K[2a]), Li/K[2-P(2-OMe-Ph)2-cyclopentanesulfonate] (Li/K[2b]), and H[2b], and the corresponding Pd(II) alkyl complexes (κ2-P,O-2a)PdMe(pyridine) (3a) and (κ2-P,O-2b)PdMe(pyridine) (3b) is described herein. The sulfonate-bridged base-free dimer {(2b)PdMe}2 (4b) was synthesized by abstraction of pyridine from 3b using B(C6F5)3. The borane-coordinated base-free dimer [{2b·B(C6F5)3}PdMe]2 (5b), in which B(C6F5)3 binds to a sulfonate oxygen, was prepared by addition of 1 equiv of B(C6F5)3 per Pd to 4b or addition of 2 equiv of B(C6F5)3 to 3b. Compounds 3b, 4b, and 5b polymerize ethylene with low activity (up to 210 kg mol–1 h–1 at 250 psi and 80 °C) to linear polyethylene (Mn = 1950–5250 Da) with predominantly internal olefin placements. 3b and 4b copolymerize ethylene with methyl acrylate to linear copolymers that contain up to 11.7 mol % methyl acrylate, which is incorporated as –CH2CH(CO2Me)CH2– (80%) in-chain units and –CH2CH(CO2Me)Me (8%) and –CH2CH=CH(CO2Me) (12%) chain-end units. 3b and 4b also copolymerize ethylene with vinyl fluoride to linear copolymers that contain up to 0.41 mol % vinyl fluoride, which is incorporated as –CH2CHFCH2– (~80%) in-chain units and –CH2CF2H (7%), –CH2CHFCH3 (5%), and –CH2CH2F (8%) chain-end units. Complexes 3b and 4b are more stable and active in ethylene polymerization than analogous (PAr2-CH2CH2SO3)PdR catalysts, but are less active than analogous (PAr2-arenesulfonate)PdR catalysts. Low-temperature NMR studies show that 4b reacts with ethylene below -10 °C to form the ethylene adduct cis-P,R-(2b)PdMe(ethylene) (7b), which undergoes ethylene insertion at 5 °C. DFT calculations for a model (PMe2-cyclopentanesulfonate)Pd(Pr)(ethylene) species show that ethylene insertion proceeds by cis-P,R/trans-P,R isomerization followed by migratory insertion, and that the lower activity of 3b and 4b vis-à-vis analogous (PAr2-arenesulfonate)PdR catalysts results from a higher barrier for migratory insertion of the trans-P,R isomer.},
doi = {10.1021/acs.organomet.7b00572},
journal = {Organometallics},
issn = {0276-7333},
number = 17,
volume = 36,
place = {United States},
year = {2017},
month = {8}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 12 works
Citation information provided by
Web of Science

Save / Share: