7137-98-6

Upstream product

• 7137-96-4 2-methyl-N-(1-pyridin-2-yl-ethylidene)-aniline 
• 95-53-4 o-toluidine 
• 1122-62-9 2-acetylpyridine 

Relevant academic research and scientific papers

Highly Stereoregular 1,3-Butadiene and Isoprene Polymers through Monoalkyl- N-Aryl-Substituted Iminopyridine Iron Complex-Based Catalysts: Synthesis and Characterization

Some novel monoalkyl-N-aryl-substituted iminopyridine iron chloride complexes, differing in the nature of the substituent at the iminic carbon and at the ortho position of the aryl ring, were synthesized and characterized. For one of them, single crystals were obtained, which allowed for the determination of its crystalline structure, in which the iron center is coordinated to the chlorides and to the two nitrogen atoms of the ligand. The coordination around iron is distorted tetrahedral, a coordination mode rarely identified for FeCl2 adducts with bidentate nitrogen ligands. All the complexes were used, in combination with methylaluminoxane, for the polymerization of 1,3-butadiene and isoprene, providing syndiotactic 1,2 poly(1,3-butadiene)s and poly(isoprene)s with a predominantly cis-1,4/3,4 alternating structure, in which short cis-1,4 sequences of three or five units, whose length depends on the nature of the ligand on the iron atom, are present. A detailed NMR characterization (1H-, 13C-, and 2D experiments) of the resultant poly(isoprene)s is reported, and a tentative scheme for the formation of the novel isoprene polymers is proposed.

PROCESS FOR PREPARING CONJUGATED DIENE (CO)POLYMERS IN THE PRESENCE OF A CATALYTIC SYSTEM COMPRISING A PYRIDYL IRON (III) COMPLEX

A process for preparing conjugated diene (co)polymers comprising polymerizing at least one conjugated diene in the presence of a catalytic system comprising: (a) at least one pyridyl iron (III) complex having general formula (I) or (II): wherein: —R1, R2, R3 and R4, identical or different, represent a hydrogen atom; or are selected from linear or branched, optionally halogenated C1-C20, preferably C1-C15, alkyl groups, optionally substituted cycloalkyl groups, optionally substituted aryl groups; —R5 represents a hydrogen atom, or is selected from linear or branched, optionally halogenated C1-C20, preferably C1-C15, alkyl groups, optionally substituted cycloalkyl groups, optionally substituted aryl groups; —X, identical or different, represent a halogen atom such as, for example, chlorine, bromine, iodine; or are selected from linear or branched C1-C20, preferably C1-C15, alkyl groups, —OCOR6 groups or —OR6 groups wherein R6 is selected from linear or branched C1-C20, preferably C1-C15, alkyl groups. —n is 3; (b) at least one co-catalyst selected from organo-aluminum derivatives, preferably from: (b1) aluminum compounds having general formula (III): Al(R7)(R8)(R9) (IIl) wherein R7 represents a hydrogen atom, or is selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, aryl groups, alkylaryl groups, arylalkyl groups, alkoxy groups; R8 and R9, identical or different, are selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, aryl groups, alkylaryl groups, arylalkyl groups; (b2) aluminoxanes having general formula (IV): (R10)2—Al—O—[-AI(R11)—O-]m-AI-(R12)2 (IV), wherein R10, R11 and R12, identical or different, represent a hydrogen atom, or a halogen atom such as chlorine, bromine, iodine, fluorine; or are selected from linear or branched C1-C20 alkyl groups, cycloalkyl groups, aryl groups, said groups being optionally substituted with one or more silicon or germanium atoms; and m is an integer ranging from 0 to 1000; (b3) partially hydrolyzed organo-aluminum derivatives; (b4) haloaluminum alkyls having general formula (V) or (VI): AI(R13)p(X′)3-p (V) AI2(R13)q(X′)3-q (VI) wherein p is 1 or 2; q is an integer ranging from 1 to 5; R13, identical or different, are selected from linear or branched C1-C20 alkyl groups; X′ represents a chlorine or bromine atom, preferably chlorine; provided that said co-catalyst (b) is not selected from organo-boron derivatives.