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Showing papers by "George M. Sheldrick published in 1985"


Book
01 Dec 1985
TL;DR: The latest in a series on crystallographic computing, this collection of 33 papers covers the full spectrum of computer applications in crystallography, including the use of micro-, mini-, and mainframe computers.
Abstract: The latest in a series on crystallographic computing, this collection of 33 papers covers the full spectrum of computer applications in crystallography, including the use of micro-, mini-, and mainframe computers. Special emphasis is given to single crystal and powder data collection, including position sensitive detectors; to crystallographic databases; to computer methods in protein crystallography; and to program systems for crystal structure determination. Presented at the Ninth International School on Crystallographic Computing, held in Mulheim (FRG) in August 1984, these papers provide state-of-the-art information that is not available elsewhere.

190 citations


Journal ArticleDOI
TL;DR: In this paper, the crystal structure of the complex [{Au(PPh3)}2{µ-C(Pph3)CO2Et}]ClO4 has been determined: space group P21/c, with a= 18.666(6), b= 17.490(5), c= 16.413(5)A, β 95.10(3)°, and R= 0.055.
Abstract: Phosphonium salts (Ph3PCH2CO2R)ClO4(R = Me or Et) react with [Au(acac)L′](acac = acetylacetonate, L′= PPh3 or AsPh3), displacing acac as acetylacetone and yielding cationic complexes of the corresponding phosphorus ylides L (L = Ph3PCHCO2Me, L′= PPh3; L = Ph3PCHCO2Et, L′= PPh3 or AsPh3). These complexes react with [Au(acac) L′] to give dinuclear species [(AuL′)2{µ-C(PPh3)CO2R}]ClO4(R = Et, L′= PPh3 or AsPh3; R = Me, L′= PPh3). The displacement of the ligand tetrahydrothiophene (tht) in [AuCl(tht)] by the ylides Ph3PCHCO2R (R = Me or Et) forms complexes [AuCl(L)], which react (i) with chlorine to give [AuCl3L] or (ii) with L in the presence of NaClO4 to give complexes [AuL2]ClO4, which also react with chlorine to form gold(III) complexes [AuCl2L2]ClO4. The crystal structure of the complex [{Au(PPh3)}2{µ-C(PPh3)CO2Et}]ClO4 has been determined: space group P21/c, with a= 18.666(6), b= 17.490(5), c= 16.413(5)A, β 95.10(3)°, and R= 0.055. A short Au ⋯ Au contact of 2.892(2)A is observed.

66 citations


Journal ArticleDOI
TL;DR: In this article, the perhalogenated 1,2,3,5-dithiadiazolium salts were derived by methathesis from ClCN2S2+Cl− with AgF2.
Abstract: Synthesen der perhalogenierten 1,2,3,5-Dithiadiazolium-Salze FCN2S2+Cl− (5) (durch Metathese aus ClCN2S2+Cl− mit AgF2), FCN2S2+AsF6− (5a) (aus 5 und AgAsF6), CF3CN2S2+Cl− (11) (aus CF3CN und S3N3Cl3 in fl. SO2 (bei dieser Reaktion werden als Nebenprodukte u.a. S5N5+FeCl4− (9), S4N4O2 (10), CF3CN3S2Cl2 (11a) und CF3CN4S3+S3N3O4− (12) isoliert) und BrCN2SCl− (15) (aus 13c und SO2Cl2) werden mitgeteilt. Durch Reduktion von XCN2S2+(Cl, Br)− mit Zn in fl. SO2 entstehen die entsprechenden Radikale XCN2S (13a–d, X = F, Cl, Br, CF3) in hohen Ausbeuten. Diese Radikale sind im festen Zustand diamagnetisch. Durch Umsetzung von 13b und d mit den ihnen zugrunde liegenden Chloriden lassen sich definierte Verbindungen der Zusammensetzung (XCN2S2)3Cl (16a, b, X = Cl, CF3) erhalten. Bei der Umsetzung von ClCN2S2+SbCl6− mit 13b erfolgt dagegen Reduktion des Anions unter Bildung von (ClCN2S2+)2 SbCl52− (17). Die Strukturen von 13d und 16b wurden durch Rontgen-, die von 13d auserdem durch Elektronenbeugung in der Gasphase bestimmt. Zum Verstandnis der gefundenen Strukturen und der gemessenen ESR-Spektren von 13 wurden Modellrechnungen nach der MNDO-Methode an dem RCN2S2-System sowie an den moglichen Dimeren von 13 durchgefuhrt. Perhalogenated 1,2,3,5-Dithiadiazolium Salts and 1,2,3,5-Dithiadiazoles Syntheses of the perhalogenated 1,2,3,5-dithiadiazolium salts FCN2S2+Cl− (5) (by methathesis from ClCN2S2+Cl− with AgF2), FCN2S2+AsF6− (5a) (from 5 and AgAsF6), CF3CN2S2+Cl (11) (from CF3CN and S3N3Cl3 in liquid SO2 (in this reaction the by-products S5N5+Cl4− (9), S4N4O2 (10), CF3CN3S2Cl2 (11a), and CF3CN4S3+S3N3O4− (12) are isolated, too), and BrCN2SCl− (15) (from 13c and SO2Cl2) are reported. By reduction of XCN2S2+ (Cl, Br)− with Zn in liquid SO2 the corresponding radicals XCN2S (13a – d, X = F, Cl, Br, CF3) are formed in high yields. These radicals are diamagnetic in the solid state. From 13b and d and their corresponding chlorides distinct compounds of the composition (XCN2S2)3Cl (16a, b, X = Cl, CF3) are obtained, while in the reaction of 13b with ClCN2S2+SbCl6 only reduction of the anion under formation of (ClCN2S2+)2SbCl52− (17) occurs. Structures of 13d and 16b were determined by X-ray-, of 13d also by electron-diffraction in the vapour phase. In order to understand the observed structures and ESR spectra of 13, model calculations by the MNDO method were performed for the RCN2S2-system and also for possible dimers there of.

65 citations



Journal ArticleDOI
TL;DR: Le compose du titre cristallise dans le systeme orthorhombique, groupe Pna2 1 and sa structure est affinee jusqu'a R=0,064 as discussed by the authors.
Abstract: Le compose du titre cristallise dans le systeme orthorhombique, groupe Pna2 1 et sa structure est affinee jusqu'a R=0,064

46 citations


Journal ArticleDOI
TL;DR: N-acyl-enaminecarbaldehydes 6a - g with an electron accepting group in the α- position react in a hetero-Diels-Alder cycloaddition with enolethers to 4-amino- dihydropyrans, which represents a convenient entry to branched aminosugars of the garosamine-type.

35 citations


Journal ArticleDOI
TL;DR: In this article, the crystal structures of diphenyl-N-(p-toluenesulphonyl)selenimide, (1), and 5,6-dimethyl-2,1,3-benzoselenadiazole, (8) have been determined by X-ray diffraction.
Abstract: SeCl4 reacts with Ph3PNSiMe3(2) by elimination of SiMe3Cl to form Ph3PNSeCl3(3), which is converted to (Ph3PN)2SeCl2(4) by a further mole of (2). Compound (4) may also be prepared from (2) and SeOCl2, or Se2Cl2; (4) reacts with SbCl5 to form [(Ph3PN)2SeCl]+[SbCl6]–(5). 2,4,6-Tri-t-butylaniline and SeOCl2 give chloro-N-(4,6-di-t-butyl-2-oxocyclohexa-3,5-dien-1-ylidene)selenamide, (7). Compounds (3),(4),(5), and (7), the previously reported diphenyl-N-(p-toluenesulphonyl)selenimide, (1), and 5,6-dimethyl-2,1,3-benzoselenadiazole, (8), have been studied by 77Se n.m.r.; the crystal structures of (1), (3), (4), and (7) have been determined by X-ray diffraction. The Se–N bond lengths of 1.787(6), 1.680(4), 1.735(4), and 1.766(4)A all indicate significant Se–N multiple bonding when compared with Se–N bonds from the literature, but curiously the longest of the four is in (1), the only structure containing a formal double bond. Although bond length alternation indicates that the quinone type resonance extreme predominates for (7), the Se–N and Se–O distances are shorter than in an analogous compound, N-(3,5-dimethyl-2-oxocyclohexa-3,5-dien-1-ylidene)phenylselenamide, the Se–O distance being reduced by 0.5 A to 2.079(3)A.

32 citations



Journal ArticleDOI
TL;DR: In this article, the reaction of NSF 1 with LiN(SiMe3)R′ (R′ = CMe3, SiMe3), linear [e.g., B.
Abstract: Aus der Umsetzung von NSF 1 mit LiN(SiMe3)R′ (R′ = CMe3, SiMe3) werden lineare [z. B. (Me3CNSN)2S (11), Me3CNSNCMe3 (14), Me3SiNSNSiMe3 (17), (Me3Si)2NSNSNSiMe3 (19)] und cyclische Thiazene (S4N5F (22)) isoliert, die Umsetzung von 1 mit 17 im Molverhaltnis 2:1 liefert (S3N4)n (23) in hohen Ausbeuten. Strukturvorschlage fur 23 werden diskutiert; die Umsetzung von 23 mit AsF5 liefert S4N4 · AsF5 (24) in einer bisher nicht bekannten Modifikation. Reaktionsmoglichkeiten der terminalen SN-Gruppe werden diskutiert und die Strukturuntersuchungen an 11 und 24 mitgeteilt. Reaction of Thiazylfluoride with Multifunctional Nitrogen Derivatives From the reaction of NSF 1 with LiN(SiMe3)R′ (R′ = CMe3, SiMe3), linear [e. g. (Me3CNSN)2S (11), Me3CNSNCMe3 (14), Me3SiNSNSiMe3 (17), (Me3Si)2NSNSNSiMe3 (19)] and cyclic thiazenes (S4N5F (22)) are isolated, (S3N4)n (23) is obtained in high yield from 1 and 17 (in the ratio 2:1). Possible structures for 23 are discussed; the reaction of 23 with AsF5 gives S4N4 · AsF5 (24) in a hitherto unknown modification. Possible reactions of the terminal SN groups are discussed and the structures of 11 and 24 are reported.

21 citations




Journal ArticleDOI
TL;DR: In this paper, the reaction of hexafluoropropanimine derivatives (CF3)2CNC(CF32OM)2OM (2a, b) (MNa, K), wahrscheinlich CF32CN- als Zwischenstufe was investigated.
Abstract: NaSCN und KOCN reagieren mit Hexafluoraceton (HFA) im Molverhaltnis 1:2 unter Abbau des Anions in einem Schritt zu den Hexafluorpropanimin-Derivaten (CF3)2CNC(CF3)2OM (2a, b) (MNa, K), wahrscheinlich uber (CF3)2CN– als Zwischenstufe. Die Hydrolyse von 2a in Gegenwart wasriger Tetraphenylphosphoniumchlorid-Losung ergibt ein kristallines Hydrat der Zusammensetzung[(CF3)2C(OH)2·(CF3)2C(O)OH]– Ph4P+ (3). Im Kristall liegen dimere Dianionen vor, die uber vier asymmetrische und zwei symmetrische Wasserstoff-Bruckenbindungen verknupft sind. In einer unubersichtlichen Reaktion entsteht bei einem Reaktandenverhaltnis KSCN/HFA von 1:1 die polycylische Bisspiroverbindung 5. Kaliumselenocyanat reagiert mit HFA unter C – Se-Bindungsspaltung und nachfolgender Bildung des CF3-substituierten Oxazolidins 6. Die Rontgenstrukturanalysen von 2a, 3, 5 und 6 werden mitgeteilt. Reactions of Hexafluoroacetone with Alkali Cyanates NaSCN and KOCN react with hexafluoroacetone (HFA) in a molar ratio of 1:2 in a one-step reaction to yield the hexafluoropropanimine derivatives (CF3)2CNC(CF3)2OM (2a, b) (MNa, K). (CF3)2CN– is a possible intermediate. Hydrolysis of 2a in aqueous tetraphenylphosphonium chloride solution yields a crystalline hydrate of composition [(CF3)2C(OH)2·(CF3)2C(O)OH]– Ph4P+ (3). In the solid state dimeric dianions are observed, which are connected via four asymmetrical and two symmetrical O H O bonds. Starting with a 1:1 KSCN/HFA stoichiometry the polycyclic bisspiro compound 5 is formed in a complex reaction. In the reaction of potassium selenocyanate with HFA the C–Se bond is cleaved and the CF3-substituted oxazolidine 6 is formed. The X-ray structure analyses of 2a, 3, 5 and 6 are reported.

Journal ArticleDOI
TL;DR: The results of X-ray analyses of crystalline 2-t-butyl-6-(2,6-dimethylphenyl)-3,5-diphenyl-1,4-dithia-2, 6-diaza-3, 5-diborinanes are reported and correlated as mentioned in this paper.

Journal ArticleDOI
TL;DR: The crystal structure of 2,4,4-trifluoro-1,3-dithietan-2-ylium Hexafluoroarsenate is described in this paper.
Abstract: Crystal Structure of 2,4,4-Trifluoro-1,3-dithietan-2-ylium Hexafluoroarsenate Crystals of [F2CS2CF]⊕ [AsF6]⊖ are orthorhombic, space group Pmmn, with a = 764.9(1), b = 831.7(1), c = 690.3(1) pm. The cation possesses mm symmetry and does not show any short intermolecular interactions. The CF and CS bonds to the cationic carbon are significantly shorter than the other CF and CS bonds. The anion exhibits twofold disorder.

Journal ArticleDOI
TL;DR: Synthese du (dicyano-1,1 oxo-2 trifluoro) propanure and du(dicyno-fluoro-1 tricyanofluoro-2,3,3 allylideneamino) methanure
Abstract: Synthese du (dicyano-1,1 oxo-2 trifluoro) propanure et du (dicyano-fluoro-1 tricyano-2,3,3 allylideneamino) methanure

Journal ArticleDOI
TL;DR: In this paper, a tricyclic system with a central fourteen-membered ring is proposed, where disilylated amines (Me3Si)2NR (RMe, Ph, SiMe3).
Abstract: Die Titelverbindung CISCF2CF2SCI 1 reagiert mit disilylierten Aminen (Me3Si)2NR (RMe, Ph, SiMe3) glatt zu 1,3,2-Dithiazolidinen (3a–c). Bei der Umsetzung mit (Me3SiNR)2SO2 (RMe, SiMe3) werden die 1,3,5,2,4-Trithiadiazepane 4a, b erhalten; mit N,N′-disilyliertem Harnstoff bildet sich das 1,5,2,4-Dithiadiazepanon 5. CISCF2CF2SSCI und SO2[N(SiMe3)2]2 reagieren zum achtgliedrigen 1,2,4,6,3,5-Tetrathiadiazocan 6. Durch Anwendung des Verdunnungsprinzips wird mit disilyliertem Piperazin 7 im Molverhaltnis 1:1 der sechzehngliedrige Ring 9 synthetisiert, welcher zwei Piperazineinheiten im Ringgerust enthalt. Von 1,3,5,2,4-Trithiadiazepan-Tetraphenylphosphoniumchlorid 10 wird die Rontgenstrukturanalyse mitgeteilt. 4b reagiert mit 1 zu 11; hier liegt ein zehngliedriger Ring vor, der durch eine SO2-Gruppe uberbruckt ist. Bei veranderter Reaktionsfuhrung erhalt man ein Produkt der doppelten Molekulmasse, dem eine tricyclische Struktur zugeschrieben wird, die einen zentralen vierzehngliedrigen Ring enthalt (13). Tetrafluoro-1,2-ethanedisulfenyl Dichloride – a Precursor for new Sulfur-Nitrogen-Carbon Heterocycles 1,3,2-Dithiazolidines (3a–c) are obtained by reaction of the title compound CISCF2CF2SCI 1 with disilylated amines (Me3Si)2NR (RMe, Ph, SiMe3). Reaction with (Me3-SiNR)2SO2 (RMe, SiMe3) yields 1,3,5,2,4-trithiadiazepanes 4a, b, whereas N,N′-disilylated urea leads to the dithiadiazepanon 5. CISCF2CF2SSCI and SO2[N(SiMe3)2]2 react to yield the eight-membered tetrahiadiazocane 6. Using the dilution principle, with disilylated piperazine 7 in a molar ratio of 1:1 the sixteen-membered ring 9 is formed, which contains two piperazine units within the ring skeleton. The crystal structure of 1,3,5,2,4-trithiadiazepane-tetraphenylphosphonium chloride 10 is reported. 4b reacts with 1 to yield 11 in which a ten-membered ring is bridged by an SO2 group. By changing the reaction conditions a product of twice the molecular weight is formed, for which a tricyclic system with a central fourteen-membered ring 13 is proposed.


Journal ArticleDOI
TL;DR: In this paper, a complex L − du titre forment des complexes inertes avec les metaux dans leurs etats d'oxydation inferieurs.
Abstract: Les complexes L − du titre forment des complexes inertes avec les metaux dans leurs etats d'oxydation inferieurs. Preparation et structure cristalline du complexe de Rh

Journal ArticleDOI
TL;DR: In this article, triethylamine is used to catalyze the reaction of Hexafluoroacetone (HFA) with Nitriles of main groups V and VI elements.
Abstract: Hexafluoraceton (HFA) reagiert mit Nitrilen der V. Hauptgruppe, wie CF3P(CN)2 (1), P(CN)3 (2) und Sb(CN)3 (3), unter Spaltung der E CN-Bindungen zu den Verbindungen 4 – 6. Triethylamin katalysiert die unter milden Bedingungen ablaufenden Reaktionen. Ein vollstandig anderer Reaktionstyp wird im Fall des Se(CN)2 beobachtet; hier wird ein Molekul Triethylamin in die entstehende Verbindung 7 eingebaut. As(NCS)3 addiert je zwei Molekule HFA uber die C N-Dreifachbindung zum symmetrischen Trithioarsenit (8). Von 4, 7 und 8 werden die Kristallstrukturen mitgeteilt. Reactions of Hexafluoroacetone with Nitriles of Main Groups V and VI Hexafluoroacetone (HFA) reacts with nitriles of group V elements like CF3P(CN)2 (1), P(CN)3 (2), and Sb(CN)3 (3) via E CN bond cleavage to yield compounds 4 – 6. The reactions are catalyzed by triethylamine and proceed under mild conditions. A completely different reactivity is observed for Se(CN)2, where triethylamine is incorporated into the resulting compound 7. As(NCS)3 adds two molecules of HFA per ligand across the C N triple bond forming the symmetric trithioarsenite (8). The crystal structures of 4, 7, and 8 are reported.

Journal ArticleDOI
TL;DR: The structure of [Cl(C6F5)2Au{Ph2PCH (AuNC5H5) PPh2}AuCl] has been determined by X-ray diffraction: space group P, a=11.664(5), b=14.790(6), c= 18.344(6)A, α=111.30(4), β= 94.1 8(4); Z= 2; R= 0.075 for 4 627 reflections as discussed by the authors.
Abstract: The reaction of [Au(C6F5)2(Ph2PCHPPh2)] with [AuX(L)][X = Cl or Br, L = tetrahydrothiophen (tht) or AsPh3] leads to trinuclear complexes [X(C6F5)2Au{Ph2PCH (AuL) PPh2}AuX] containing the tridentate [Ph2PCH PPh2]– ligand. Displacement of tht with L = PPh3, pyridine, or 4-methylpyridine leads to the corresponding derivatives. The structure of [Cl(C6F5)2Au{Ph2PCH (AuNC5H5) PPh2}AuCl] has been determined by X-ray diffraction: space group P, a=11.664(5), b=14.790(6), c= 18.344(6)A, α=111.30(4), β= 94.1 8(4), γ=107.64(4)°, and Z= 2; R= 0.075 for 4 627 reflections.

Journal ArticleDOI
TL;DR: The first example of isonitrile elimination in palladium chemistry was reported in this article, where the splitting of the imidoyl bridges is accompanied by an isomerization of the group from the syn to the anti conformation as shown by a single crystal X-ray diffraction study of trans-Pd{C(C 6 F 5 )N(Me)}Cl(CNMe) 2 ].

Journal ArticleDOI
TL;DR: Le premier compose cristallise dans le systeme monoclinique, groupe P2 1 /n, and le second dans the systeme orthorhombique, group Pbca, are described in this paper, where atomes W et Mo sont a environ 0,09 A and 0,12 A respectivement en dehors du plan forme par les atomes N et S


Journal ArticleDOI
TL;DR: In this article, the carbon atom of the iso-nitrile isomer was inserted into the four-membered [CS]₂ ring to give compounds such as P(CN), AsR′₃ (3), FP(S)R′(4), PhP(S), R′2 (5), BuᵗAsR′ ₂ (6), and GeR′∆ (7) respectively.
Abstract: Cyanides such as P(CN)₃ , As(CN)₃ , PhP(CN)₂ , BuᵗAs(CN)₂ and Ge(CN)₄ react with [(CF₃)₂CS]₂ (1) by insertion of the carbon atom of the iso-nitrile isomer into the four-membered [CS]₂ ring to give compounds PR′₃ (2), AsR′₃ (3), FP(S)R′₂ (4), PhP(S)R′2 (5), BuᵗAsR′₂ (6) and GeR′₄ (7) respectively, where R′ is the novel heterocyclic ligand[xxx]. The crystal structures of 3 and 7 are reported.

Journal ArticleDOI
TL;DR: The reaction of N,N-dichlorophenylsulphonamide with tungsten hexacarbonyl in refluxing CCl₄ leads in good yield to the yellow polymeric complex, which may be converted to the octahedral nitrene complex by recrystallisation from aceto-nitrile as mentioned in this paper.
Abstract: The reaction of N,N-dichlorophenylsulphonamide with tungsten hexacarbonyl in refluxing CCl₄ leads in good yield to the yellow polymeric complex [(PhSO₂N)₂WCl₂]ₓ, which may be converted to the octahedral nitrene complex [(PhSO₂N)₂WCl₂(CH₃CN)₂] by recrystallisation from aceto­nitrile. Crystals of the acetonitrile complex are triclinic, space group P 1, a = 820.7(2), b = 1128.8(3), c = 1286.9(3) pm, α = 89.25(3), β = 89.54(3). γ = 72.67(2)°, Z = 2, R = 0.027 for 2527 unique observed reflections.

Journal ArticleDOI
TL;DR: In this article, the reaction between AgAsF6 and phenylphosphine proceeds with formation of a phosphorus-phosphorus bond, and the main product is characterized by an X-ray structure determination.
Abstract: Abstract The reaction between AgAsF6 and phenylphosphine proceeds with formation of a phosphorus-phosphorus bond. The main product 1, [(C6H5)PH2Ag{μ-(C6H5PH)2}]2 (AsF6)2, was characterized by an X-ray structure determination [P1̄, a = 919.0(4), b = 1109.8(4), c = 1316.4(5) pm, α = 97.48(3), β = 107.25(3), γ = 102.71(3)°, Z = 1, R = 0.057 for 2806 observed reflections], 1 contains Ag2P4 rings; the silver atoms are further coordinated by phenylphosphine ligands, thus acquiring trigonal coordination geometry. A similar reaction is observed with Cu(AsF6)2, forming the analogous Cu(I) complex 2.

Journal ArticleDOI
TL;DR: Piperidine-N-oxyboranes and 2,2,6,6-Tetramethylpiperidine -noxyborane have been prepared starting from halogenoboranes by three methods: a) by reaction with N-hydroxypiperidine and triethylamine; b) by cleavage of the Si -O-bond in piperidine n-oxy-trimethylsilanes; and c) by reactivation with metallated Piperidine N-oxy compounds as discussed by the authors.
Abstract: Piperidine-N-oxyboranes and 2,2,6,6-Tetramethylpiperidine-N-oxyboranes have been prepared starting from halogenoboranes by three methods: a) By reaction with N-hydroxypiperidine and triethylamine; b) by cleavage of the Si -O-bond in piperidine-N-oxy-trimethylsilanes and c) by reaction with metallated piperidine-N-oxy compounds. Diboryloxides and diborylamides, resp., are obtained upon reaction of piperidine-N-oxybrom oboranes with hexamethyldisiloxane and hexamethyldisilazane. Steric influences upon reactivity and spectroscopic properties are discussed. The compounds are characterized by elemental analysis, mass and NMR spectroscopy (1H , 11B , 13C, 14N, 29Si). An X-ray analysis has been carried out for tris(2,2,6,6-tetram ethylpiperidine-1-oxy)borane 13.

Journal ArticleDOI
TL;DR: The dinitrogen-tetrafluoroborato complex (Ph3P)2(Cl)(N2)(H)IrFBF3 reacts with 9-m ethylguanine in CH2Cl2 to give [(Ph 3P]2Cl)(H]Ir(9-methyl guanine)]+BF4- (2) as mentioned in this paper.
Abstract: The dinitrogen-tetrafluoroborato complex (Ph3P)2(Cl)(N2)(H)IrFBF3 reacts with 9-m ethylguanine in CH2Cl2 to give [(Ph3P)2(Cl)(H)Ir(9-methylguanine)]+BF4- (2). From a solution of 2 in methanol the complex (Ph3P)2(Cl)2(H)Ir(9-methylguanine) (3) is obtained. The reaction of [(Ph3P)2(Cl)(N2)(H)IrOSO2C4F9] with 9-methylguanine affords the com plexes [(Ph3P)2(Cl)(N2)(H)Ir(9-methylguanine)]+C4F9SO3- (5) and [(Ph3P)2(Cl)(H2O)(H)Ir(9-methylguanine)]+ C4F9SO3- (6). The coordination of the guanine derivative to the iridium atom in 2, 5, 6 is discussed on the basis of the infrared spectra. The crystal structure of 3 was determined. 9-Methylguanine is coordinated via N (7). Intermolecular hydrogen bonding between the chloro-ligand and HN (1) of guanine leads to linear chains in the crystal.

Journal ArticleDOI
TL;DR: Dithiooxamide 1 reacts with hexafluoroacetone 2 at room temperature to yield 1,1, 1,3, 3,3-hexafluoromethyl-methyl group from hexaflooracetone, the migration of oxygen and the elimination of sulfur as discussed by the authors.
Abstract: Dithiooxamide 1 reacts with hexafluoroacetone 2 at room temperature to yield 1,1,1,3,3,3-hexafluoro-2-propylamino-1-thiooxamide 3 and sulfur. The modes of formation of the bis(trifluoromethyl)-methyl group from hexafluoroacetone, the migration of oxygen and the elimination of sulfur are not clear. Crystals of 3 are monoclinic, space group Cc, with a = 2865.3(13), b = 924.4(9), c = 702.9(6) pm, β = 93.3(7)°. The structure was refined to R = 0.067 from 614 reflections

Journal ArticleDOI
TL;DR: In this article, the crystal structure of the methanol solvate of (1) was determined, and it possesses twofold symmetry, with Au -O 206.3, Au -P 221.6 pm, and β = 99.90°.
Abstract: Abstract The reaction between (triphenylphosphine)acetatogold(I) and concentrated sulphuric acid in methanol leads to (Ph3PAu)2SO4 (1) or [(Ph3PAu)3O]+ HSO4- , depending on the acid concentration. The crystal structure of the methanol solvate of (1) was determined [C2/c, a = 1348.3(2), b = 1451.0(2), c = 1853.8(3) pm, β = 99.90(2)°, Z = 4, R = 0.037 for 3138 unique observed reflections], 1 possesses crystallographic twofold symmetry, with Au -O 206.3, Au -P 221.6 pm. The corresponding selenate is isomorphous.