Unveiling meta-Alkyloxy/-Silyloxy-Substituted N-Aryl PNP Ligands for Efficient Cr-Catalyzed Ethylene Tetramerization

Samir Barman; Nestor Garcia; E. A. Jaseer; Mohamed Elanany; Motaz Khawaji; Hassan Alasiri; Abdul Malik P. Peedikakkal; Muhammad Naseem Akhtar; Rajesh Theravalappil

doi:10.1021/acsomega.3c03029

Unveiling meta-Alkyloxy/-Silyloxy-Substituted N-Aryl PNP Ligands for Efficient Cr-Catalyzed Ethylene Tetramerization

Samir Barman^*, Nestor Garcia, E. A. Jaseer^*, Mohamed Elanany, Motaz Khawaji, Hassan Alasiri, Abdul Malik P. Peedikakkal, Muhammad Naseem Akhtar, Rajesh Theravalappil

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

4 Scopus citations

Abstract

Novel N-aryl-functionalized PNP ligands (1-4) bearing m-alkyloxy/-silyloxy substituents were prepared and evaluated for chromium-catalyzed ethylene oligomerization using MMAO-3A as an activator. The selected Cr/PNP system under optimized condition exhibited high 1-octene-selective (up to 70 wt %) ethylene tetramerization at a remarkable rate (over 3000 kg gCr^-1 h^-1). More importantly, the undesirable polyethylene selectivity was restricted to a minimum level of ∼1-2 wt % for pre-catalysts derived with ligands 1 and 2. Employing chlorobenzene as a reaction medium yielded best productivity in conjunction to the total α-olefin (1-C₆ + 1-C₈) selectivity (∼88 wt %). N-aryl PNP ligands (3 and 4) incorporating m-silyloxy substituents in the phenyl ring exhibited relatively poorer tetramerization performance while yielding higher PE fraction as compared to their m-alkyloxy derivatives. A detailed molecular structure of the best-performing pre-catalyst 1-Cr was established by single-crystal X-ray diffraction analysis. The stability of 1/Cr-based catalyst system was investigated for a reaction time of up to 2 h under optimized condition.

Original language	English
Pages (from-to)	26437-26443
Number of pages	7
Journal	ACS Omega
Volume	8
Issue number	29
DOIs	https://doi.org/10.1021/acsomega.3c03029
State	Published - 25 Jul 2023

Bibliographical note

Funding Information:
The authors acknowledge the support provided by the Saudi Aramco for funding the project # CRP02285. The support of King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia is highly appreciated.

Publisher Copyright:
© 2023 The Authors. Published by American Chemical Society

ASJC Scopus subject areas

General Chemistry
General Chemical Engineering

Access to Document

10.1021/acsomega.3c03029

Cite this

@article{befab6369a974d158b12d9f4b13601b4,

title = "Unveiling meta-Alkyloxy/-Silyloxy-Substituted N-Aryl PNP Ligands for Efficient Cr-Catalyzed Ethylene Tetramerization",

abstract = "Novel N-aryl-functionalized PNP ligands (1-4) bearing m-alkyloxy/-silyloxy substituents were prepared and evaluated for chromium-catalyzed ethylene oligomerization using MMAO-3A as an activator. The selected Cr/PNP system under optimized condition exhibited high 1-octene-selective (up to 70 wt %) ethylene tetramerization at a remarkable rate (over 3000 kg gCr-1 h-1). More importantly, the undesirable polyethylene selectivity was restricted to a minimum level of ∼1-2 wt % for pre-catalysts derived with ligands 1 and 2. Employing chlorobenzene as a reaction medium yielded best productivity in conjunction to the total α-olefin (1-C6 + 1-C8) selectivity (∼88 wt %). N-aryl PNP ligands (3 and 4) incorporating m-silyloxy substituents in the phenyl ring exhibited relatively poorer tetramerization performance while yielding higher PE fraction as compared to their m-alkyloxy derivatives. A detailed molecular structure of the best-performing pre-catalyst 1-Cr was established by single-crystal X-ray diffraction analysis. The stability of 1/Cr-based catalyst system was investigated for a reaction time of up to 2 h under optimized condition.",

author = "Samir Barman and Nestor Garcia and Jaseer, {E. A.} and Mohamed Elanany and Motaz Khawaji and Hassan Alasiri and Peedikakkal, {Abdul Malik P.} and Akhtar, {Muhammad Naseem} and Rajesh Theravalappil",

note = "Funding Information: The authors acknowledge the support provided by the Saudi Aramco for funding the project # CRP02285. The support of King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia is highly appreciated. Publisher Copyright: {\textcopyright} 2023 The Authors. Published by American Chemical Society",

year = "2023",

month = jul,

day = "25",

doi = "10.1021/acsomega.3c03029",

language = "English",

volume = "8",

pages = "26437--26443",

journal = "ACS Omega",

issn = "2470-1343",

publisher = "American Chemical Society",

number = "29",

}

TY - JOUR

T1 - Unveiling meta-Alkyloxy/-Silyloxy-Substituted N-Aryl PNP Ligands for Efficient Cr-Catalyzed Ethylene Tetramerization

AU - Barman, Samir

AU - Garcia, Nestor

AU - Jaseer, E. A.

AU - Elanany, Mohamed

AU - Khawaji, Motaz

AU - Alasiri, Hassan

AU - Peedikakkal, Abdul Malik P.

AU - Akhtar, Muhammad Naseem

AU - Theravalappil, Rajesh

N1 - Funding Information: The authors acknowledge the support provided by the Saudi Aramco for funding the project # CRP02285. The support of King Fahd University of Petroleum & Minerals (KFUPM), Dhahran, Saudi Arabia is highly appreciated. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society

PY - 2023/7/25

Y1 - 2023/7/25

N2 - Novel N-aryl-functionalized PNP ligands (1-4) bearing m-alkyloxy/-silyloxy substituents were prepared and evaluated for chromium-catalyzed ethylene oligomerization using MMAO-3A as an activator. The selected Cr/PNP system under optimized condition exhibited high 1-octene-selective (up to 70 wt %) ethylene tetramerization at a remarkable rate (over 3000 kg gCr-1 h-1). More importantly, the undesirable polyethylene selectivity was restricted to a minimum level of ∼1-2 wt % for pre-catalysts derived with ligands 1 and 2. Employing chlorobenzene as a reaction medium yielded best productivity in conjunction to the total α-olefin (1-C6 + 1-C8) selectivity (∼88 wt %). N-aryl PNP ligands (3 and 4) incorporating m-silyloxy substituents in the phenyl ring exhibited relatively poorer tetramerization performance while yielding higher PE fraction as compared to their m-alkyloxy derivatives. A detailed molecular structure of the best-performing pre-catalyst 1-Cr was established by single-crystal X-ray diffraction analysis. The stability of 1/Cr-based catalyst system was investigated for a reaction time of up to 2 h under optimized condition.

AB - Novel N-aryl-functionalized PNP ligands (1-4) bearing m-alkyloxy/-silyloxy substituents were prepared and evaluated for chromium-catalyzed ethylene oligomerization using MMAO-3A as an activator. The selected Cr/PNP system under optimized condition exhibited high 1-octene-selective (up to 70 wt %) ethylene tetramerization at a remarkable rate (over 3000 kg gCr-1 h-1). More importantly, the undesirable polyethylene selectivity was restricted to a minimum level of ∼1-2 wt % for pre-catalysts derived with ligands 1 and 2. Employing chlorobenzene as a reaction medium yielded best productivity in conjunction to the total α-olefin (1-C6 + 1-C8) selectivity (∼88 wt %). N-aryl PNP ligands (3 and 4) incorporating m-silyloxy substituents in the phenyl ring exhibited relatively poorer tetramerization performance while yielding higher PE fraction as compared to their m-alkyloxy derivatives. A detailed molecular structure of the best-performing pre-catalyst 1-Cr was established by single-crystal X-ray diffraction analysis. The stability of 1/Cr-based catalyst system was investigated for a reaction time of up to 2 h under optimized condition.

UR - http://www.scopus.com/inward/record.url?scp=85166776717&partnerID=8YFLogxK

U2 - 10.1021/acsomega.3c03029

DO - 10.1021/acsomega.3c03029

M3 - Article

AN - SCOPUS:85166776717

SN - 2470-1343

VL - 8

SP - 26437

EP - 26443

JO - ACS Omega

JF - ACS Omega

IS - 29

ER -

Unveiling meta-Alkyloxy/-Silyloxy-Substituted N-Aryl PNP Ligands for Efficient Cr-Catalyzed Ethylene Tetramerization

Abstract

Bibliographical note

ASJC Scopus subject areas

Access to Document

Fingerprint

Cite this