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Full-Text Articles in Chemical Engineering
N-Type Polythiophenes, Li Jia
Submicron Surface Patterning Using Interfacial Colloidal Particle Self-Assembly, Li Jia
Submicron Surface Patterning Using Interfacial Colloidal Particle Self-Assembly, Li Jia
Li Jia
No abstract provided.
The Role Of Phosphine In Cobalt-Catalyzed Carbonylative Polymerization Of N-Alkylaziridines, Li Jia
The Role Of Phosphine In Cobalt-Catalyzed Carbonylative Polymerization Of N-Alkylaziridines, Li Jia
Li Jia
A series of CH3COCo(CO)3L complexes (1, L = PCy3; 2, L = PMe2Ph; 3, L = PPh3; 4, L = P(para-F-Ph)3; 5, L = P(meta-F-Ph)3; and 6, L = P(ortho-tolyl)3) were studied as precatalyst for the title polymerization. The Co–P bond length primarily responds to the cone angle of the phosphine ligand (6 > 1 > 2 ≈ 3 ≈ 4 ≈ 5), while the back-donation to the axial acetyl ligand and the equatorial CO ligand depends on the electron-donating ability of the phosphine and increases in the order 1 > 6 > 2 > 3 > 4 > 5. The equilibrium constant for CH3COCo(CO)3L + CO …
Micropatterning By Non-Densely Packed Interfacial Colloidal Crystals, Li Jia
Micropatterning By Non-Densely Packed Interfacial Colloidal Crystals, Li Jia
Li Jia
A new surface-patterning method that involves the intact transferring of interfacial non-densely packed hexagonal colloidal crystals onto silicon wafer substrates has been developed. The arrays have long-range order on the square millimeter scale. The laser diffraction pattern of a micropatterned surface is shown in the figure.
Dynamic Self-Assembling. Linear Periodic Structure Generated By Evaporation Of Colloidal Solution On Flat Surface, Li Jia
Li Jia
No abstract provided.
Carbonylative Copolymerization Of Azetidines And Tetrahydrofuran. Dual Role Of Azetidine And Synthesis Of Poly(Amide-Co-Ester) With Periodic Ester Distribution, Li Jia
Li Jia
No abstract provided.
Mechanistic Studies Of The Copolymerization Reaction Of Aziridines And Carbon Monoxide To Produce Poly-Beta-Peptoids, Li Jia
Li Jia
The coupling of carbon monoxide and aziridines has been shown to be selective for comonomer-alternating enchainment in the presence of PhCH2C(O)Co(CO)4 to afford poly-beta-peptoids. In this article, we have investigated the mechanistic aspects of the reaction of CO and N-butylaziridine by means of in situ infrared spectroscopy employing CH3C(O)Co(CO)3L (L = PPh3 (1) and P(o-tolyl)3 (2)) as precatalysts. Precatalyst 1 exists in solution under catalytic conditions as an equilibrium mixture of 1 and CH3C(O)Co(CO)4, and affords both poly-beta-butylalanoid and the corresponding lactam. By way of contrast, precatalyst 2 which possesses the sterically bulky and labile P(o-tolyl)3 ligand, affords only the …
Design Of Carbonylative Polymerization Of Heterocycles. Synthesis Of Polyesters And Poly(Amide-Block-Ester)S, Li Jia
Li Jia
No abstract provided.
Stereochemistry Of Cobalt-Catalyzed Carbonylation Of 2-Oxazolines, Li Jia
Stereochemistry Of Cobalt-Catalyzed Carbonylation Of 2-Oxazolines, Li Jia
Li Jia
The stereospecificity of the title reaction is studied using the (4R,5S)-4-methyl-2,5-diphenyl-2-oxazoline and (4R,5R)-4-methyl-2,5-diphenyl-2-oxazoline as the substrates. While the catalyst system containing BnCo(CO)4 and BnCOCo(CO)4 (1) was used initially, a convenient catalyst formulation generated from the commercially available Co2(CO)8 and AIBN (2) has been found more effective than catalyst system 1. The stereoselectivity in all cases favors inversion at the C(5)-position with diastereomeric excess up to >97%.