| Nickel belongs toⅧfamily of transition metals.Because of its fine coordination activity and relatively low price,it has been widely used in organic synthesis,industrial catalysis,etc.Trivalent phosphine as a strong ligand can form stable complexes with transition metals,and can be widely found in organometallic conpouds.Organonickel compound supported by trimethylphosphine has high reaction activity and selectivity.1.Application of electron-rich nickel(0) and cobalt(0) complexes supported by trimethylphosphine in C-Cl bond activationChloroarenes are the important intermediates in organic synthesis,and they have been used in industry,agriculture,leather,pharmaceutical and other industries.Because of they are inexpensive and readily available,replacing the more expensive aryl bromide, iodide as raw materials will have significant economic value.The disposal of organic wastes containing halogen has become a major environmental and social problem,because most of them are toxic and thermally stable,accumulating in the surroundings for long time periods.Mastery of the activation of C-Cl bond will help us to find a new chlorination,dechlorination and C-Cl bond key functional way,and help us solve the serious environmental problems.Reactions of Ni(PMe3)4 with substrates containing imine anchoring groups(1-4,11 -13,17,18),proceed by oxidative addition of the C-Cl bond to give rise to the organo nickel(Ⅱ) complexes(5-8,14-16,19,20),respectively.A simple and convenient synthetic method for some novel bis(isoindolinone)(21-24,33-35) starting from aryl chlorides is described by reaction of phenylimines with stoichiometric amounts of tetrakis(trimethylphosphine)nickel(0) under 1 bar of CO at room temperature.The formation mechanism was proposed and discussed.We discovered that the reaction of the phenyl-imines with stoichiometric amounts of (η4-1,2:5,6-cyclooctadiene)bis(trimethylphosphine)nickel(0),(Ni(PMe3)2(COD)),under a CO atmosphere(1 bar) at room temperature could rapidly proceed to give the desired bis(isoindolinone) product in good yields.In addition,we attempted the reaction of the phenyl imines with stoichiometric amounts of tetrakis(trimethylphosphine)cobalt(0) under a CO atmosphere(1 bar) at room temperature,it also proceed to give the desired bis(isoindolinone) product.2.Application of nickel complexes supported by trimethylphosphine in C-F bond activationThe study of C-F bond activation has important significance and value.Mastery of the activation of C-F bond will help us to study the new fluorinated organic synthesis,and to solve the increasingly serious problem of environmental pollution.Reactions of Ni(PMe3)2(COD) with fluorinated compounds containing imine as anchoring group afforded one novel culster complex 37.During the functionalization, we attempted the reaction of fluorinated phenylimines with Ni(PMe3)2(COD) under 1 bar of CO,and we wanted to find a new way of preparation of carbonyl compounds.Reactions of Ni(PMe3)2(COD)with pentafluoropyridine in mild conditions afforded C-F activated products,without anchoring groups.During the reaction of Ni(PMe3)2(COD) with octafluoronaphthalene,theπcoordinated intermediates(46,47) were isolated.The C-F bond may be activated according to change the conditions,such as temperature, solvents,pressure and so on.3.Application of nickel complexes supported by trimethylphosphine in C-CN bond activationThe activation of C-C bonds has great value in petrochemical,materials,organic synthesis,and so on.At present,most of such reactions required long time heat even at pressurized conditions,and accompanied by side reactions and environmental pollution. The activation of C-C bonds under mild conditions is currently a very meaningful topic.The reaction of Ni(PMe3)4 and Ni(PMe3)2(COD) with substituted benzonitriles lead to C-C bond cleavage under mild conditions.And we attempted the reactions of benzonitrile nickel(Ⅱ) complexes with bromobenzene and carbon monoxide,respectively.4.Synthesis and properties of nickel(Ⅱ) complexes containing trimethylphosphine and thiophenolato-ligandsMetal thiolate complexes are involved in fundamental catalytic(e.g. hydrodesulfurization) and biological(e.g.iron-sulfur proteins) process.The reaction of[NiMe2(PMe3)3]with two molar equivalents of substituted thiophenols gave rise to[Ni(SAr)2(PMe3)2](Ar=phenyl(54),2-methylphenyl(55), 4-methoxyphenyl(56)).The possible reaction mechanism has been proposed,and the intermediate was successfully isolated.The reactions of nickel thiolate compounds with CO and PhCH were discussed.The reaction of[NiMe2(PMe3)3]with substituted 2-mercaptobenzaldehyde gave rise to organonickel(Ⅱ) complexes(61,62).The reactions of organonickel(Ⅱ) complexes with iodomethane were primarily studied.All of the new complexes are characterized by IR,1H NMR,13C NMR and 31P NMR. Structures of some compounds have been confirmed by X-ray diffraction techniques.
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