NÚMEROS DE OXIDAÇÃO EM COMPOSTOS ORGÂNICOS

Oxidation numbers in organic compounds

– Considering the fact that didactic textbooks almost do not discuss this topic, a method of evaluation of the oxidation numbers of carbon atoms in organic compounds is presented here. This method is applied to different types of reactions including biochemical processes to illustrate the sites of oxidation, reduction or disproportionation. Potential confusion between the oxidation numbers and the charges or formal charges is also discussed in this article.

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Então, carga formal de um átomo é a carga que o átomo adquiriria quando as ligações que faz com outros átomos são quebradas homoliticamente >@ Compara-se o nú-mero de eletrões de valência do átomo na molécula com o número de eletrões de valência no átomo neutro.

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56, usando hidreto de tributilestanho 69.

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74 8VDQGRRIRUPDOLVPRGDYDULDomRGRQ~PHURGHR[LGD-omRWDPEpPVHSHUFHEHVHUXPDR[LGDomRSRLVDPXGDQoD GRVQR[HP74HHP75pGHSDUD

2V R[LGDQWHV ELROyJLFRV 1$'_(NADP_{) 76 WUDQVIRUPDP}

os substratos 78HPSURGXWRV80>@,JQRUDPRVDTXL RV DVSHWRV HVWHUHRTXtPLFRV TXDO R iWRPR GH KLGURJpQLR pró-R ou pró-STXHpUHPRYLGRHP78HTXDOpRODGRre ou siGRiWRPRSUyTXLUDOCTXHpDWDFDGRHP76/77ePDLV IiFLOYLVXDOL]DUHVWDUHDomRXVDQGRDHVWUXWXUDGHUHVVRQkQ-cia 77.

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2+H[LJHWUDQVIHUrQFLDGHDSHQDVXPHOHWUmR2EVHUYDQ-do o equilíbrio 86 87SHUFHEHVHTXHRFRUUHXUHGXomR R[LGDomRGRViWRPRVDHDFRPDWURFDGHGRLVHOHWU}HV 3RUpPRVHTXLOtEULRV86 88 e 88 87 LPSOLFDPDWUR-FD GH XP HOHWUmR SRU SDVVR H DSHQDV HVWHV SURFHVVRV VmR LPSRUWDQWHV GXUDQWH D QHXWUDOL]DomR GH UDGLFDLV OLYUHV e SUHFLVRPHQFLRQDUTXHRVVLVWHPDV1$'1$'+H1$'3 1$'3+VmRFDSD]HVGHWURFDUH[FOXVLYDPHQWHXPSDUGH HOHWU}HV2XWURVVLVWHPDVGHUHGXomRR[LGDomRHPVLVWHPDV YLYRVVmRGLVFXWLGRVQDOLWHUDWXUDHVSHFLDOL]DGD>@ Glutationa 89>@XPWULSHSWtGHRTXHDWXDFRPRDQ-WLR[LGDQWH WHP XP JUXSR °6+ QD VXD FRPSRVLomR 'RLV JUXSRV °6+ GH GXDV PROpFXODV GH JOXWDWLRQD FHGHP GRLV iWRPRVGHKLGURJpQLRSDUDVHOLJDUHPDXPiWRPRGHR[L-JpQLR H VRIUHP R[LGDomR 'D PHVPD IRUPD DV UHGXWDVHV GHULERQXFOHRWtGHRV>@XVDPRVVHXVGRLVJUXSRV°6+ SUHVHQWHVHPXPGRVFHQWURVDWLYRVSDUDSURPRYHUUHPR-omRGHJUXSR°2+GDSRVLomRGHULERQXFOHRWtGHRV90 e IRUPDUGHVR[LUULERQXFOHRWtGHRV91RVFRPSRQHQWHVGRV iFLGRVGHVR[LUULERQXFOHLFRV

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