The uncatalysed decarboxylation of 3-oxoglutaric acid, HO2C·CH2·CO·CH2·CO2H → CH3·CO·CH2·CO2H + CO2 has been studied at 42°. The rate constants for the un-ionised acid, the monoanion, and the dianion are 12 × 10–3 min–1, 45 × 10–3 min–1, and 2·75 × 10–3 min–1 respectively. Because of the higher reactivity of the monoanion, the pH-rate profile for the uncatalysed decarboxylation is bell-shaped with a rate maximum at pH 3·5 (l= 0·1M). The enhanced reactivity of the monoanion appears to be due to intramolecular hydrogen bonding between the carbonyl group and the un-ionised carboxy-group. The practical ionisation constants of 3-oxoglutaric acid are pK1= 3·23 and pK2= 4·27 at 0·01M. The decarboxylation of 3-oxoglutaric acid, unlike that of acetoacetic acid, is catalysed by transition-metal ions, so that in the presence of metal ions there is a rapid loss of one molecular equivalent of carbon dioxide followed by a slower loss of a second molecular equivalent in the uncatalysed reaction. The catalytic effects of copper(II), nickel(II), and manganese(II) have been studied in some detail. It has been found that 2,2′-bipyridyl which is capable of π-bonding with the metal ions enhances the catalytic activity of manganese(II) by a factor of 10 while the effect with copper(II) and nickel(II) is less marked (ca. 2 times). The possible significance of these effects in the action of the metal-activated decarboxylases is discussed, as manganese(II) is the biologically important metal ion in the enzymatic reactions.
{"title":"The uncatalysed and metal-ion catalysed decarboxylation of 3-oxoglutaric acid: a model for an enzyme system","authors":"R. Hay, K. N. Leong","doi":"10.1039/J19710003639","DOIUrl":"https://doi.org/10.1039/J19710003639","url":null,"abstract":"The uncatalysed decarboxylation of 3-oxoglutaric acid, HO2C·CH2·CO·CH2·CO2H → CH3·CO·CH2·CO2H + CO2 has been studied at 42°. The rate constants for the un-ionised acid, the monoanion, and the dianion are 12 × 10–3 min–1, 45 × 10–3 min–1, and 2·75 × 10–3 min–1 respectively. Because of the higher reactivity of the monoanion, the pH-rate profile for the uncatalysed decarboxylation is bell-shaped with a rate maximum at pH 3·5 (l= 0·1M). The enhanced reactivity of the monoanion appears to be due to intramolecular hydrogen bonding between the carbonyl group and the un-ionised carboxy-group. The practical ionisation constants of 3-oxoglutaric acid are pK1= 3·23 and pK2= 4·27 at 0·01M. The decarboxylation of 3-oxoglutaric acid, unlike that of acetoacetic acid, is catalysed by transition-metal ions, so that in the presence of metal ions there is a rapid loss of one molecular equivalent of carbon dioxide followed by a slower loss of a second molecular equivalent in the uncatalysed reaction. The catalytic effects of copper(II), nickel(II), and manganese(II) have been studied in some detail. It has been found that 2,2′-bipyridyl which is capable of π-bonding with the metal ions enhances the catalytic activity of manganese(II) by a factor of 10 while the effect with copper(II) and nickel(II) is less marked (ca. 2 times). The possible significance of these effects in the action of the metal-activated decarboxylases is discussed, as manganese(II) is the biologically important metal ion in the enzymatic reactions.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79805390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The complex InL3(L = 3-hydroxy-2-methyl-4-pyronato-anion) has been prepared, and its n.m.r., i.r. and Raman spectra compared with those of the parent ligand. Polarographic reduction of this complex, and of In(trop)3(trop = tropolonato-anion) takes place in successive one-electron steps, as in the case of complexes of indium with bidentate sulphur-donor ligands. One-electron polarographic reduction of In (acac)3(acac = acetylacetonato-anion) and In(oxine)3(oxine = quinolin-8-olato-anion) has also been observed, and may be a general property of complexes of indium(III) with bidentate chelating ligands.
{"title":"Co-ordination compounds of indium. Part XI. The stepwise one-electron reduction of some neutral indium(III) complexes","authors":"D. G. Tuck, M. K. Yang","doi":"10.1039/J19710003100","DOIUrl":"https://doi.org/10.1039/J19710003100","url":null,"abstract":"The complex InL3(L = 3-hydroxy-2-methyl-4-pyronato-anion) has been prepared, and its n.m.r., i.r. and Raman spectra compared with those of the parent ligand. Polarographic reduction of this complex, and of In(trop)3(trop = tropolonato-anion) takes place in successive one-electron steps, as in the case of complexes of indium with bidentate sulphur-donor ligands. One-electron polarographic reduction of In (acac)3(acac = acetylacetonato-anion) and In(oxine)3(oxine = quinolin-8-olato-anion) has also been observed, and may be a general property of complexes of indium(III) with bidentate chelating ligands.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79806557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Glidewell, D. Rankin, A. Robiette, G. Sheldrick, S. M. Williamson
The molecular structure of bis-(trifluoromethyl)nitroxyl, (CF3)2NO, has been determined in the vapour phase by the sector microphotometer electron diffraction method. Principal structural parameters with estimated standard deviations in parentheses are: r(NO) 1·26(3), r(CN) 1·441(8), and r(CF) 1·320(4)A; F–C–F 109·8°(1·0°), C–N–C 120·9°(2·0°), C–N–O 117·2°(0·6°). The angle between the CNC plane and the NO bond is 22°(3°).
{"title":"Molecular structure of bis(trifluoromethyl)nitroxyl: an electron diffraction study","authors":"C. Glidewell, D. Rankin, A. Robiette, G. Sheldrick, S. M. Williamson","doi":"10.1039/J19710000478","DOIUrl":"https://doi.org/10.1039/J19710000478","url":null,"abstract":"The molecular structure of bis-(trifluoromethyl)nitroxyl, (CF3)2NO, has been determined in the vapour phase by the sector microphotometer electron diffraction method. Principal structural parameters with estimated standard deviations in parentheses are: r(NO) 1·26(3), r(CN) 1·441(8), and r(CF) 1·320(4)A; F–C–F 109·8°(1·0°), C–N–C 120·9°(2·0°), C–N–O 117·2°(0·6°). The angle between the CNC plane and the NO bond is 22°(3°).","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79241897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ab initio SCF–MO calculations on PH3BH3, PF3BH3, and PF3O are described. In the borane complexes, the predominant mode of bonding involves σ-donation from the phosphine with very little π-back-bonding. In the oxide, both σ-donation and π-back-bonding are important, the latter involving to a large extent the 3d-phosphorus orbitals.
{"title":"An ab initio study of the bonding in phosphine borane, trifluorophosphine broane and trifluorophosphine oxide","authors":"I. H. Hillier, V. Saunders","doi":"10.1039/J19710000664","DOIUrl":"https://doi.org/10.1039/J19710000664","url":null,"abstract":"Ab initio SCF–MO calculations on PH3BH3, PF3BH3, and PF3O are described. In the borane complexes, the predominant mode of bonding involves σ-donation from the phosphine with very little π-back-bonding. In the oxide, both σ-donation and π-back-bonding are important, the latter involving to a large extent the 3d-phosphorus orbitals.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79396374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cobalt(II) salts react with 1,2-bis(dimethylarsino)ethylene (edas)(ca. 90%trans, 10%cis) under u.v. irradiation to give complexes of cis-edas in good yield. The intermediate complexes of trans-edas are generally unstable, but a black compound Col2(trans-edas)2 with one unpaired electron can be isolated; this probably contains bridging ligand groups in a polymeric structure. The cobalt(II) complexes CoX2(cis-edas)2(X = Cl, Br, I, or NO3), which have one unpaired electron, are probably five-co-ordinate in solution and tetragonally distorted octahedral in the solid state. The complex CoCl2(cis-edas) appears to consist of the planar cation [Co(cis-edas)2]2+ and the tetrahedral anion [CoCl4]2– in the solid state, but attempts to prepare [Co(cis-edas)3]2+ give only the tervalent derivative [Co(cis-edas)3]3+. The cobalt(II) halogeno-complexes of cis-edas are readily oxidised to cobalt(III) complexes of the type [CoX2(cis-edas)2]Y [X = Cl or Br; Y = Cl, Br, or PF6; X = NCS, Y = PF6 or Co(SCN)4] The chemical and physical properties of the cobalt–cis-edas complexes are generally very like those of the analogous complexes of o-phenylenebis(dimethylarsine).
{"title":"Complexes of Bi- and ter-valent nickel with olefinic ditertiary arsines","authors":"M. Bennett, J. Wild","doi":"10.1039/J19710000536","DOIUrl":"https://doi.org/10.1039/J19710000536","url":null,"abstract":"Cobalt(II) salts react with 1,2-bis(dimethylarsino)ethylene (edas)(ca. 90%trans, 10%cis) under u.v. irradiation to give complexes of cis-edas in good yield. The intermediate complexes of trans-edas are generally unstable, but a black compound Col2(trans-edas)2 with one unpaired electron can be isolated; this probably contains bridging ligand groups in a polymeric structure. The cobalt(II) complexes CoX2(cis-edas)2(X = Cl, Br, I, or NO3), which have one unpaired electron, are probably five-co-ordinate in solution and tetragonally distorted octahedral in the solid state. The complex CoCl2(cis-edas) appears to consist of the planar cation [Co(cis-edas)2]2+ and the tetrahedral anion [CoCl4]2– in the solid state, but attempts to prepare [Co(cis-edas)3]2+ give only the tervalent derivative [Co(cis-edas)3]3+. The cobalt(II) halogeno-complexes of cis-edas are readily oxidised to cobalt(III) complexes of the type [CoX2(cis-edas)2]Y [X = Cl or Br; Y = Cl, Br, or PF6; X = NCS, Y = PF6 or Co(SCN)4] The chemical and physical properties of the cobalt–cis-edas complexes are generally very like those of the analogous complexes of o-phenylenebis(dimethylarsine).","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81270039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The molecular structure of (π-C5H5)2Rh2Fe2(CO)8, has been determined from X-ray diffraction studies. The compound crystallizes in the centrosymmetric orthorhombic space group Pnma(D2h16, No. 62) with a= 17·979(15), b= 12·079(12), c= 9·386(8)A and Z= 4. A full three-dimensional analysis has led to the location of all non-hydrogen atoms. The structure has been refined by least-squares methods to R 7·90% for the 627 unique non-zero reflections. The molecule has crystallographically imposed Cs symmetry with the four metal atoms defining an irregular tetrahedron with Rh–Rh 2·648(3), Rh–Fe 2·570(5)–2·598(5), and Fe–Fe 2·539(7)A. The π-C5H5 ligands and a bridging carbonyl group are associated with the two rhodium atoms while there are three terminal CO ligands attached to Fe(1) and two to Fe(2).An unusual feature of the structure is the presence of two asymmetric carbonyl bridges, Fe(2)–CO–Rh and Fe(2)–CO–Rh′, with Fe–C 1·79(4) and Rh–C 2·18(3)A. The overall disposition of ligands around the tetrahedral metal-atom core is such that it proves impossible to assign 18 outer valence electrons to each metal atom.
{"title":"Crystal structure of tri-µ-carbonyl-pentacarbonylbis-(π-cyclopentadienylrhodio)di-iron(Rh–Rh)(Fe–Fe)(4Rh–Fe), (π-C5H5)2Rh2Fe2(CO)8","authors":"M. R. Churchill, M. V. Veidis","doi":"10.1039/J19710002170","DOIUrl":"https://doi.org/10.1039/J19710002170","url":null,"abstract":"The molecular structure of (π-C5H5)2Rh2Fe2(CO)8, has been determined from X-ray diffraction studies. The compound crystallizes in the centrosymmetric orthorhombic space group Pnma(D2h16, No. 62) with a= 17·979(15), b= 12·079(12), c= 9·386(8)A and Z= 4. A full three-dimensional analysis has led to the location of all non-hydrogen atoms. The structure has been refined by least-squares methods to R 7·90% for the 627 unique non-zero reflections. The molecule has crystallographically imposed Cs symmetry with the four metal atoms defining an irregular tetrahedron with Rh–Rh 2·648(3), Rh–Fe 2·570(5)–2·598(5), and Fe–Fe 2·539(7)A. The π-C5H5 ligands and a bridging carbonyl group are associated with the two rhodium atoms while there are three terminal CO ligands attached to Fe(1) and two to Fe(2).An unusual feature of the structure is the presence of two asymmetric carbonyl bridges, Fe(2)–CO–Rh and Fe(2)–CO–Rh′, with Fe–C 1·79(4) and Rh–C 2·18(3)A. The overall disposition of ligands around the tetrahedral metal-atom core is such that it proves impossible to assign 18 outer valence electrons to each metal atom.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81703980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Crystals of the title compound are monoclinic, space group P21/a, with Z= 4 in a unit cell of dimensions: a= 11·18, b= 15·52, c= 15·48 A, and β= 114° 05′. Diffractometer data were used and the structure refined to R 0·080 for 1419 independent reflections. The ruthenium atoms each carry three carbonyl groups and are bonded to one another at the corners of an isosceles triangle. The two equal sides (2·776A) are unbridged, but the apical atom is equidistant from, and π-bonded to, three consecutive atoms C(1)–(3) of the cyclododecatrienyl ligand which thus form a π-allyl group. The outer two atoms of this π-allyl group are also each σ-bonded to one of the basal ruthenium atoms. Rearrangement of the bonds in the cyclododeca-1,5,9-triene ligand occurs, as the complex contains ethylenic links at C(6)–C(7) and at C(9)–C(10). The distance between the two basal metal atoms (2·92 A) is longer than the base–apex distances; this bond is probably hydrogen-bridged. In this compound, therefore, the cyclododecatrienyl ligand functions as a five-electron donor. The mean Ru–C and C–O distances for the carbonyl ligands are 1·87 and 1·17 A respectively.
{"title":"Crystal and molecular structure of nonacarbonyl(cyclododecatrienetriyl)hydrido-triangulo-triruthenium, HRu3(CO)9(C12H15): a ruthenium cluster with a novel allyl bonding system to the cyclododecatrienetriyl ligand","authors":"A. Cox, P. Woodward","doi":"10.1039/J19710003599","DOIUrl":"https://doi.org/10.1039/J19710003599","url":null,"abstract":"Crystals of the title compound are monoclinic, space group P21/a, with Z= 4 in a unit cell of dimensions: a= 11·18, b= 15·52, c= 15·48 A, and β= 114° 05′. Diffractometer data were used and the structure refined to R 0·080 for 1419 independent reflections. The ruthenium atoms each carry three carbonyl groups and are bonded to one another at the corners of an isosceles triangle. The two equal sides (2·776A) are unbridged, but the apical atom is equidistant from, and π-bonded to, three consecutive atoms C(1)–(3) of the cyclododecatrienyl ligand which thus form a π-allyl group. The outer two atoms of this π-allyl group are also each σ-bonded to one of the basal ruthenium atoms. Rearrangement of the bonds in the cyclododeca-1,5,9-triene ligand occurs, as the complex contains ethylenic links at C(6)–C(7) and at C(9)–C(10). The distance between the two basal metal atoms (2·92 A) is longer than the base–apex distances; this bond is probably hydrogen-bridged. In this compound, therefore, the cyclododecatrienyl ligand functions as a five-electron donor. The mean Ru–C and C–O distances for the carbonyl ligands are 1·87 and 1·17 A respectively.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81735302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The complexes AlCl3,2Me2O,AlCl3,1·5MeCN, AlCl3,2MeCN, and AlCl31·5HCO2Me have been examined by i.r. and Raman spectroscopy; model calculations support a trigonal-bipyramidal five-co-ordinate structure for AlCl3,2Me2O but ionic structures are suggested for the others. AlCl3,2MeCN has uncombined MeCN in the crystal lattice.
{"title":"The spectra and structure of aluminium chloride complexes. Part IV. Structure of higher complexes of aluminium chloride","authors":"D. E. Jones, J. Wood","doi":"10.1039/J19710003135","DOIUrl":"https://doi.org/10.1039/J19710003135","url":null,"abstract":"The complexes AlCl3,2Me2O,AlCl3,1·5MeCN, AlCl3,2MeCN, and AlCl31·5HCO2Me have been examined by i.r. and Raman spectroscopy; model calculations support a trigonal-bipyramidal five-co-ordinate structure for AlCl3,2Me2O but ionic structures are suggested for the others. AlCl3,2MeCN has uncombined MeCN in the crystal lattice.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81834897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Difluorophosphino(tetrafluorophosphoranyl)methylamine, PF2·NMe·PF4, and difluorophosphino(difluorophosphoryl)methylamine, PF2·NMe·POF2, result from the action of difluorophosphino(trimethylsilyl)methylamine on phosphorus pentafluoride and phosphoryl trifluoride respectively. Difluorophosphino(trimethylsilyl)methylamine can be prepared in good yield from chlorodifluorophosphine and heptamethyldisilazene. An alternative route to difluorophosphino(difluorophosphoryl)methylamine is the reaction between methylaminophosphoryl difluoride and chlorodifluorophosphine in the presence of base. Some other routes for these derivatives are described with the properties of these nitrogen-bridged derivatives. Comparable reactions with thionyl fluoride and sulphur dioxide do not yield products containing nitrogen bridges between phosphorus and sulphur atoms. Spectroscopic data are presented for all of these compounds.
{"title":"Preparation and characterisation of some nitrogen-bridged phosphorus fluorides","authors":"J. Harman, M. Mccartney, D. Sharp","doi":"10.1039/J19710001547","DOIUrl":"https://doi.org/10.1039/J19710001547","url":null,"abstract":"Difluorophosphino(tetrafluorophosphoranyl)methylamine, PF2·NMe·PF4, and difluorophosphino(difluorophosphoryl)methylamine, PF2·NMe·POF2, result from the action of difluorophosphino(trimethylsilyl)methylamine on phosphorus pentafluoride and phosphoryl trifluoride respectively. Difluorophosphino(trimethylsilyl)methylamine can be prepared in good yield from chlorodifluorophosphine and heptamethyldisilazene. An alternative route to difluorophosphino(difluorophosphoryl)methylamine is the reaction between methylaminophosphoryl difluoride and chlorodifluorophosphine in the presence of base. Some other routes for these derivatives are described with the properties of these nitrogen-bridged derivatives. Comparable reactions with thionyl fluoride and sulphur dioxide do not yield products containing nitrogen bridges between phosphorus and sulphur atoms. Spectroscopic data are presented for all of these compounds.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84245992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
1 : 1 Addition of trivinylborane and diboron tetrachloride gives the adduct 1,2-bis(dichloroboryl)-1-(divinylboryl)-ethane (CH2:CH)2B·CH(BCl2)·CH2BCl2(I), which reacts with BX3(X = Cl, NMe2) to give X2B·CH(BCl2)·CH2BCl2. Dehydroboration of (I) by addition of trimethylamine gives trimethylamine-divinylborane and pyrolysis gives 1,2-bisdichloroborylethylene. Similar 1 : 1 addition using diboron tetrafluoride gives an adduct with properties similar to (I).1 : 2 Addition of trivinylborane and diboron tetrachloride gives (CH2:CH)B[CH(BCl2)·CH2BCl2]2, unstable above –78°C; a similar adduct using diboron tetrafluoride has not been isolated. 1 : 3 addition does not occur with either tetrahalide.
{"title":"Reactions of trivinylborane with diboron tetrahalides: properties of some dihalogenoboryl(vinylboryl)ethanes","authors":"A. K. Holliday, R. P. Ottley","doi":"10.1039/J19710000886","DOIUrl":"https://doi.org/10.1039/J19710000886","url":null,"abstract":"1 : 1 Addition of trivinylborane and diboron tetrachloride gives the adduct 1,2-bis(dichloroboryl)-1-(divinylboryl)-ethane (CH2:CH)2B·CH(BCl2)·CH2BCl2(I), which reacts with BX3(X = Cl, NMe2) to give X2B·CH(BCl2)·CH2BCl2. Dehydroboration of (I) by addition of trimethylamine gives trimethylamine-divinylborane and pyrolysis gives 1,2-bisdichloroborylethylene. Similar 1 : 1 addition using diboron tetrafluoride gives an adduct with properties similar to (I).1 : 2 Addition of trivinylborane and diboron tetrachloride gives (CH2:CH)B[CH(BCl2)·CH2BCl2]2, unstable above –78°C; a similar adduct using diboron tetrafluoride has not been isolated. 1 : 3 addition does not occur with either tetrahalide.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84253355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}