Controlled di-lithiation enabled synthesis of phosphine-sulfonamide ligands and implications in ethylene oligomerization

2021 ◽  
Vol 50 (10) ◽  
pp. 3717-3723
Author(s):  
Nilesh R. Mote ◽  
Shahaji R. Gaikwad ◽  
Kishor V. Khopade ◽  
Rajesh G. Gonnade ◽  
Samir H. Chikkali
Keyword(s):  
Ethylene Oligomerization ◽  
Single Precursor ◽  
Pd Complexes

Arresting dilithiation intermediate at −84/−41 °C selectively produced L1A/L1B and L2A/L2B, respectively, from a single precursor. Pd-Complexes C1–C7 were prepared, fully characterized and their performance in ethylene oligomerization was studied.

Camphor-based phosphine-carbonyl ligands for Ni catalyzed ethylene oligomerization

2020 ◽  
Vol 44 (3) ◽  
pp. 1076-1081 ◽  
Author(s):  
Shabnam Behzadi ◽  
Mingjun Chi ◽  
Wenmin Pang ◽  
Tao Liang ◽  
Chen Tan
Keyword(s):  
Ethylene Oligomerization ◽  
Carbonyl Ligands ◽  
Lower Olefins ◽  
Pd Complexes ◽  
Higher Olefins

Ni and Pd complexes of camphor-based phosphine-carbonyl ligands containing biaryl moiety are designed and synthesized. The Ni complexes can catalyze ethylene oligomerization and generate waxy higher olefins as well as oily lower olefins.

Asymetrical Dimer - allyl-palladiu Complexes II. Data from Infrared Spectra and Chemical Behaviour

2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Maria Maganu ◽  
Filip Chiraleu ◽  
Constantin Draghici ◽  
Gheorghe Mihai
Keyword(s):  
Carbon Monoxide ◽  
Nmr Spectroscopy ◽  
1H Nmr ◽  
Infrared Spectra ◽  
Analytical Methods ◽  
1H Nmr Spectroscopy ◽  
Chemical Behaviour ◽  
The Asymmetry ◽  
Pd Complexes

The previous data obtained by 1H-NMR spectroscopy established the existence of an asymmetry of the bond between Pd and p-allylic groups, even in the p-allyl-Pd complexes dimers which are considered usually symmetric dimers. The asymmetry of the bond depends by the substitutes of the allylic group. Other analytical methods were investigated for additional proof of the obtained results. Thus, this paper discusses how this asymmetry would be reflected in the infrared spectra and in the reaction of the complexes with carbon monoxide.

Structural and Genetic Aspects of Proline-rich Proteins

1987 ◽  
Vol 66 (2) ◽  
pp. 457-461 ◽  
Author(s):  
A. Bennick
Keyword(s):  
General Structure ◽  
Single Gene ◽  
Conclusive Evidence ◽  
In Vitro Translation ◽  
Binding Studies ◽  
Nmr Studies ◽  
Post Translational Modifications ◽  
Single Precursor ◽  
Made In

Considerable advances have been made in the genetics of salivary proline-rich proteins (PRP). The genes for acidic, basic, and glycosylated PRP have been cloned. They code for precursor proteins that all have an acidic N-terminal followed by proline-rich repeat sequences. Structural studies on secreted proteins have demonstrated that not only acidic but also some basic PRPs have this general structure. It is possible that mRNA for different PRP may have originated from a single gene by differential mRNA splicing, but post-translational cleavages of the primary translation product apparently also occur. In vitro translation of salivary gland mRNA results in a single precursor protein for acidic PRP. Such in vitro translated protein can be cleaved by salivary kallikrein, giving rise to two commonly secreted acidic PRPs, and kallikrein or kallikrein-like enzymes may be responsible for other post-translational cleavages of PRPs. Acidic as well as some basic PRPs are phosphorylated. A protein kinase has been demonstrated in salivary glands which phosphorylates the PRPs and other secreted salivary proteins in a cAMP and Ca2+-calmodulinindependent manner. Knowledge of the conformation of PRPs is limited. There is no conclusive evidence of polyproline-like structure in the proline-rich part of PRPs. Ca2+ binding studies on acidic PRPs indicate that there is interaction between the Ca2+ binding N-terminal end and the proline-rich C-terminal part. This interaction is relieved by modification of arginine side-chains. 1H, 32P, and 43Ca NMR studies have further elucidated the conformation of acidic PRPs in solution. Present evidence shows that salivary PRPs constitute a unique superfamily of proteins which pose a number of interesting questions concerning gene structure, pre- and post-translational modifications, and protein conformation.

scholarly journals Cat-CrNP as new material with catalytic properties for 2-chloro-2-propen-1-ol and ethylene oligomerizations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jacek Malinowski ◽  
Dagmara Jacewicz ◽  
Artur Sikorski ◽  
Mariusz Urbaniak ◽  
Przemysław Rybiński ◽  
...  
Keyword(s):  
Complex Compound ◽  
Atmospheric Pressure ◽  
Room Temperature ◽  
Organometallic Compounds ◽  
Ethylene Oligomerization ◽  
High Catalytic Activity ◽  
New Material ◽  
Activity Requirement ◽  
Olefin Oligomerization ◽  
Xrd Method

AbstractThe contemporary search for new catalysts for olefin oligomerization and polymerization is based on the study of coordinating compounds and/or organometallic compounds as post-metallocene catalysts. However known catalysts are suffered by many flaws, among others unsatisfactory activity, requirement of high pressure or instability at high temperatures. In this paper, we present a new catalyst i.e. the crystalline complex compound possesing high catalytic activity in the oligomerization of olefins, such as 2-chloro-2-propen-1-ol and ethylene under very mild conditions (room temperature, 0.12 bar for ethylene oligomerization, atmospheric pressure for 2-chloro-2-propen-1-ol oligomerization). New material—Cat-CrNP ([nitrilotriacetato-1,10-phenanthroline]chromium(III) tetrahydrate) has been obtained as crystalline form of the nitrilotriacetate complex compound of chromium(III) with 1,10-phenanthroline and characterized in terms of its crystal structure by the XRD method and by multi-analytical investigations towards its physicochemical propeties The yield of catalytic oligomerization over Cat-CrNP reached to 213.92 g · mmol−1 · h−1· bar−1 and 3232 g · mmol−1 · h−1 · bar−1 for the 2-chloro-2-propen-1-ol and ethylene, respectively. Furthemore, the synthesis of Cat-CrNP is cheap, easy to perform and solvents used during preparation are environmentally friendly.

Ethylene oligomerization with 2-hydroxymethyl-5,6,7-trihydroquinolinyl-8-ylideneamine-Ni(II) chlorides

2021 ◽  
Vol 937 ◽  
pp. 121720
Author(s):  
Lei Xu ◽  
Jiaxin Li ◽  
Wenhua Lin ◽  
Yanping Ma ◽  
Xinquan Hu ◽  
...  
Keyword(s):  
Ethylene Oligomerization

scholarly journals Chimera Spectrum Diagnostics for Peptides Using Two-Dimensional Partial Covariance Mass Spectrometry

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3728
Author(s):  
Taran Driver ◽  
Nikhil Bachhawat ◽  
Leszek J. Frasinski ◽  
Jonathan P. Marangos ◽  
Vitali Averbukh ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Peptide Sequence ◽  
Two Dimensional ◽  
Peptide Ions ◽  
Finite Mass ◽  
Protein Database ◽  
Spectra Analysis ◽  
Fragment Ions ◽  
Single Precursor ◽  
The Common

The rate of successful identification of peptide sequences by tandem mass spectrometry (MS/MS) is adversely affected by the common occurrence of co-isolation and co-fragmentation of two or more isobaric or isomeric parent ions. This results in so-called `chimera spectra’, which feature peaks of the fragment ions from more than a single precursor ion. The totality of the fragment ion peaks in chimera spectra cannot be assigned to a single peptide sequence, which contradicts a fundamental assumption of the standard automated MS/MS spectra analysis tools, such as protein database search engines. This calls for a diagnostic method able to identify chimera spectra to single out the cases where this assumption is not valid. Here, we demonstrate that, within the recently developed two-dimensional partial covariance mass spectrometry (2D-PC-MS), it is possible to reliably identify chimera spectra directly from the two-dimensional fragment ion spectrum, irrespective of whether the co-isolated peptide ions are isobaric up to a finite mass accuracy or isomeric. We introduce ‘3-57 chimera tag’ technique for chimera spectrum diagnostics based on 2D-PC-MS and perform numerical simulations to examine its efficiency. We experimentally demonstrate the detection of a mixture of two isomeric parent ions, even under conditions when one isomeric peptide is at one five-hundredth of the molar concentration of the second isomer.

scholarly journals A Gain-of-Function Screen for Genes That Affect the Development of the Drosophila Adult External Sensory Organ

Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 733-752 ◽  
Author(s):  
Salim Abdelilah-Seyfried ◽  
Yee-Ming Chan ◽  
Chaoyang Zeng ◽  
Nicholas J Justice ◽  
Susan Younger-Shepherd ◽  
...  
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Cell Fate ◽  
P Element ◽  
External Support ◽  
Sensory Organ ◽  
Sensory Organs ◽  
Gain Of Function ◽  
Asymmetric Cell Divisions ◽  
Single Precursor

Abstract The Drosophila adult external sensory organ, comprising a neuron and its support cells, is derived from a single precursor cell via several asymmetric cell divisions. To identify molecules involved in sensory organ development, we conducted a tissue-specific gain-of-function screen. We screened 2293 independent P-element lines established by P. Rørth and identified 105 lines, carrying insertions at 78 distinct loci, that produced misexpression phenotypes with changes in number, fate, or morphology of cells of the adult external sensory organ. On the basis of the gain-of-function phenotypes of both internal and external support cells, we subdivided the candidate lines into three classes. The first class (52 lines, 40 loci) exhibits partial or complete loss of adult external sensory organs. The second class (38 lines, 28 loci) is associated with increased numbers of entire adult external sensory organs or subsets of sensory organ cells. The third class (15 lines, 10 loci) results in potential cell fate transformations. Genetic and molecular characterization of these candidate lines reveals that some loci identified in this screen correspond to genes known to function in the formation of the peripheral nervous system, such as big brain, extra macrochaetae, and numb. Also emerging from the screen are a large group of previously uncharacterized genes and several known genes that have not yet been implicated in the development of the peripheral nervous system.

MATHEMATICAL MODELING OF ETHYLENE OLIGOMERIZATION

1988 ◽  
pp. 1855-1860
Author(s):  
P.A. Galtier ◽  
A.A. Forestière ◽  
Y.H. Glaize ◽  
J.P. Wauquier
Keyword(s):  
Mathematical Modeling ◽  
Ethylene Oligomerization

2-Benzoimidazol-8-alkylquinolinylnickel(II) complexes as efficient catalysts for ethylene oligomerization and vinyl polymerization of norbornene

2015 ◽  
Vol 68 (21) ◽  
pp. 3825-3838 ◽  
Author(s):  
Xinfang Wei ◽  
Yunqing Jiang ◽  
Xue Cui ◽  
Yue Li ◽  
Haiwang Wang ◽  
...  
Keyword(s):  
Ethylene Oligomerization ◽  
Vinyl Polymerization
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