215459-01-1

Upstream product

• 1122-72-1 6-methyl-2-pyridinecarboxaldehyde 
• 24544-04-5 2,6-diisopropylbenzenamine 
• 1122-71-0 2-(Hydroxymethyl)-6-methylpyridine 

Downstream Products

• 454678-24-1 [pyridine-5-CH₃-2-C(H)=N(2,6-(i-C₃H₇)2C₆H₃))]palladium(II) bis-trifluoroacetate 
• 263254-74-6 N-(2,6-diisopropylphenyl)-N-(pyridin-2-ylmethyl)amine 
• 1221072-78-1 2,6-diisopropyl-N-((6-methylpyridin-2-yl)methyl)benzenamine 
• 305806-31-9 dichloro(2,6-bis(1-methylethyl)-N-[(6-methyl-2-pyridinyl)methylene]phenylamine)palladium(II) 
• 263254-77-9 di-μ-bromodibromobis(2,6-bis(1-methylethyl)-N-[(6-methyl-2-pyridinyl)methylene]phenylamine)dinickel(II) 

Relevant academic research and scientific papers

Synthesis, structures of (aminopyridine)nickel complexes and their use for catalytic ethylene polymerization

A series of α-aminopyridines in the form of (2,6-C6H 3N)(R1)(CHR2NR3R4) (R1 = R2 = H R3 = H R4 = iPr (L1a), R4 = tBu (L1b), R4 = Ph (L1c), R4 = 2,6-Me2C6H3 (L1d), R4 = 2,6-iPr2C6H3 (L1e), R1 = R2 = H R3 = R4 = Et (L1f), R1 = H R2 = Me R3 = H R4 = iPr (L2a), R4 = Ph (L2c), R4 = 2,6-Me 2C6H3 (L2d), R4 = 2,6- iPr2C6H3 (L2e), R1 = Me R2 = H R3 = H R4 = 2,6-iPr 2C6H3 (L3e)) and β-aminopyridines in the form of (2-C6H4N)(CH2CH2NR 1R2) (R1 = H R2 = iPr (4a), R2 = tBu (L4b), R1 = R2 = Et (L4f)) have been prepared. Their corresponding halonickel complexes 1a-4f are synthesized by ligand substitution from (DME)NiBr2 and the molecular structures are characterized. Four types of coordination modes include four-coordinate mononuclear species with one ligand, five-coordinate mononuclear species with two ligands, five-coordinate dinuclear species with two ligands, and a six-coordinate polymeric framework were determined by X-ray crystallography. Using methylaluminoxanes (MAO) as the activator, the nickel complexes can catalyze ethylene polymerization under moderate pressure and ambient temperature. The activity reaches 105 g PE mol-1 Ni h. The PE products with high branching and high crystallinity have M n ～ 103 with PDI 2.

Bis-alkoxycarbonylation of styrene by pyridinimine palladium catalysts

Pyridinimine-modified Pd(II) complexes of general formulae (N-N′)Pd(Y)2 catalyze the methoxycarbonylation of styrene to give dimethyl phenylsuccinate as the largely major product [N-N′ = py-2-C(R) = N(2,6-R′C6H3), R = H, Me; R′ = Me, i-Pr; 6-Mepy-2-C(H)=N[2,6-(i-Pr)2C6H3]; py-2-C(H)=N(C6H5); Y = acetate, trifluoroacetate]. The influence of various catalytic parameters on the overall conversion of styrene to carbonylated products and on the product selectivity has been studied by systematically varying the type of palladium initiator, the concentrations of organic oxidant (1,4-benzoquinone) and protic acid (p-toluenesulfonic acid), and the CO pressure. By an appropriate choice of the structure of the pyridinimine ligand and of the reaction parameters, turn-over numbers as high as 96 and selectivities in dimethyl phenylsuccinate as high as 98% were obtained. In particular, the overall conversion of styrene is controlled by the steric properties of the alkyl substituents on the imine aryl group, while the nature of the substituent (H or Me) on the imine carbon influences the selectivity. The addition of 2 equivalents of TsOH to the catalytic mixtures generally increased the styrene conversion but lowered the selectivity in dimethyl phenylsuccinate due to greater production of methyl 3,6-diphenyl-4-oxohexanoate. Further additions of TsOH (up to 6 equivalents) resulted in better selectivities and lower conversions for all precursors.