Cleavage of the carboximide CN bond promoted by reaction of camphor carboximide hydrochlorides(OC_(10)H_(15)CONHCH_(2)COOLi(H_(2)O)_(2)·2HCl(2)or OC_(10)H_(15)CONHCH(CH_(2)Ph)COOLi(H_(2)O)·HCl(3))with CuCl_(...Cleavage of the carboximide CN bond promoted by reaction of camphor carboximide hydrochlorides(OC_(10)H_(15)CONHCH_(2)COOLi(H_(2)O)_(2)·2HCl(2)or OC_(10)H_(15)CONHCH(CH_(2)Ph)COOLi(H_(2)O)·HCl(3))with CuCl_(2)leads to the corresponding amino acid complexes([Cu(H_(2)NCH_(2)COO)_(2)](I)and[Cu{H_(2)NCH(CH_(2)Ph)-COO}_(2)]·(H_(2)O)(Ⅱ)),and the camphor carboxylate residue(OC_(10)H_(15)COO^(-))which is catalytically oxidized to camphorquinone by oxygen from air.The process is mediated by coordination of the camphor carboxylate to copper.The reaction of the camphor carboximide hydrochloride(OC_(10)H_(15)CONH(CH_(2))_(2)COOLi-(H_(2)O)·HCl)(4)with CuCl_(2)follows a different trend.In this case the CN camphor carboximide bond remains intact and the complexes[CuCl{OC_(10)H_(15)CONH(CH_(2))_(2)COOLi(H_(2)O)}](Ⅲ)and[{CuCl_(2)}_(2){OC_(10)H_(15)-CONH(CH_(2))_(2)COOLi(H_(2)O)}](Ⅳ)form.However,a redox process also occurs,since formation ofⅢrequires Cu(Ⅱ)→Cu(Ⅰ)reduction as confirmed by X-ray photoelectron spectroscopy and cyclic voltammetry.A related reduction process was identified in the formation of[CuCl(OC_(10)H_(15)COOLi)](Ⅴ)from CuCl_(2)upon reaction with lithium camphor carboxylate(OC_(10)H_(15)COOLi)under nitrogen.The above results show that electron transfer is highly facilitated in the copper camphor carboximide/carboxylate system.Such an ability was used to activate oxygen from air and promote the oxidation of ethylacetoacetate to pyruvate usingⅤas the catalyst.展开更多
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文摘Cleavage of the carboximide CN bond promoted by reaction of camphor carboximide hydrochlorides(OC_(10)H_(15)CONHCH_(2)COOLi(H_(2)O)_(2)·2HCl(2)or OC_(10)H_(15)CONHCH(CH_(2)Ph)COOLi(H_(2)O)·HCl(3))with CuCl_(2)leads to the corresponding amino acid complexes([Cu(H_(2)NCH_(2)COO)_(2)](I)and[Cu{H_(2)NCH(CH_(2)Ph)-COO}_(2)]·(H_(2)O)(Ⅱ)),and the camphor carboxylate residue(OC_(10)H_(15)COO^(-))which is catalytically oxidized to camphorquinone by oxygen from air.The process is mediated by coordination of the camphor carboxylate to copper.The reaction of the camphor carboximide hydrochloride(OC_(10)H_(15)CONH(CH_(2))_(2)COOLi-(H_(2)O)·HCl)(4)with CuCl_(2)follows a different trend.In this case the CN camphor carboximide bond remains intact and the complexes[CuCl{OC_(10)H_(15)CONH(CH_(2))_(2)COOLi(H_(2)O)}](Ⅲ)and[{CuCl_(2)}_(2){OC_(10)H_(15)-CONH(CH_(2))_(2)COOLi(H_(2)O)}](Ⅳ)form.However,a redox process also occurs,since formation ofⅢrequires Cu(Ⅱ)→Cu(Ⅰ)reduction as confirmed by X-ray photoelectron spectroscopy and cyclic voltammetry.A related reduction process was identified in the formation of[CuCl(OC_(10)H_(15)COOLi)](Ⅴ)from CuCl_(2)upon reaction with lithium camphor carboxylate(OC_(10)H_(15)COOLi)under nitrogen.The above results show that electron transfer is highly facilitated in the copper camphor carboximide/carboxylate system.Such an ability was used to activate oxygen from air and promote the oxidation of ethylacetoacetate to pyruvate usingⅤas the catalyst.
