Wolfgang Haubold

Diboran(4)-Moleküle mit Boratomen unterschiedlicher Koordinationszahl/ Diborane(4) Molecules with Boron Atoms with Different Coordination Number

Abstract Molecules with directly bonded boron atoms with different coordination numbers (10, 11, 12 and 13) can be prepared from suitable bifunctional bases like 6, 7, 8 or 9 and C12B - BC12 (1) in an appropriate solvent at high dilution. Properties and spectroscopic data - including 1J(11B-11B) - are described. The molecular structure of 10 was investigated by means of an X-ray structure analysis.

Die addition von tetrahalogeno-diboran(4)-molekülen an diene

Abstract The additions of one mol of B2Cl4 or B2F4 to 1,3-butadiene yield 1,4-bis(dihalogenoboryl)-2-butene, X2BCH2CHCHCH2BX2. In the case of the chlorine compound a further molecule B2Cl4 can be added to the butene double bond. In the reaction of diboron tetrahalides with methyl-substituted conjugated or cumulated dienes we observed fast polymerisation of the hydrocarbons rather than addition reactions in almost all cases. The chemical and spectroscopic properties of the compounds are described.

2,4,6,8,9,10-Hexachlor-2,4,6,8,9,10-hexaboradamantan

The pyrolysis of alkyldichloroboranes such as MeBCl2BCHCHBCl2, Cl2BCH2BCl2 or (Cl2B)3CH at 450°C leads to the formation of hexachloro-hexaboraadamantane, C4H4B6Cl6 (I). The structure - determined by X-ray diffraction - and the spectroscopic data of 2,4,6,8,9,10-hexachloro-2,4,6,8,9,10-hexaboraadamantane are in agreement with the classical description as an organoborane, rather than as a molecule with a carborane framework. Substitution reactions are described. The bromo compound C4B4B6Br6 can be prepared by heating Me2BBr or MeBBr2 to 520°C.

Ein neuer Zugang zu halogenierten Carboranen

The copyrolysis of tetrahalogenodiborane(4) (B2X4, X = Cl, Br) or the halogenated carbon compounds such as CX4 or C2X4 yields the new carboranes C2B5X7 and C2B7Cl9 in addition to the vinyl compound C2Br3BBr2 as some of the products.

REAKTIONEN DES PYRIDINIUM-FLUOR-DITHIOPHOSPHORSÄURE-BETAINS

Abstract Pyridinium-fluor-dithiophosphorsaure-betain (1) reagiert mit Hydrazin unter Bildung von Pyridinium-hydrazin-bis(fluor-dithiophosphate) (3), mit Phenylhydrazin unter Bildung von Pyridinium-phenylhydrazido-fluordithiophosphat (5). 3 und 5 konnen mit Methyljodid in die entsprechenden S-Methylester 7 und 8 uberfuhrt werden. Die Umsetzung der Titelverbindung 1 mit H2S fuhrt zu Pyridinium-difluor-pentathiodiphosphat (9). Das primare Hydrolyseprodukt von 1 ist nicht stabil. Mercaptane und 1 reagieren zu den Pyridiniumsalzen der Fluor-trithiophosphorsaure-monoester (10), die durch Umsetzung mit Methyljodid in die Fluor-trithiophosphorsaure-diester (12) umgewandelt werden konnen. Die Reaktion von Phenyl-t-butyl-phosphan mit 1 hat eine P–P-Verknupfung zur Folge. Reaktionsprodukt ist Pyridinium-phenyl-t-butyl-phosphido-fluor-dithiophosphat (13). Pyridinium-fluoro-dithiophosphoric betaine (1) reacts with hydrazine to give pyridinium hydrazine bis(fluoro-dithiophosphate) (3), with phenylhydrazine to give pyri...

Borylierung von Sulfamiden, Sulfoniminen und Sulfondiiminen/Borylation of Sulfamides, Sulfonimines and Sulfonediimines

Abstract The diborylated sulfamide 6a can be obtained from 2-chloro-1,3-dimethyl-1,3,2-diazaborolidine and the silylated sulfamide la , whereas (Me2N)2BCl and 1a yield the dithia-tetrazadiborocine 7b. Similarly, (Me2N)2BCl reacts with a) the sulfonimine 2a, b) the sulfonediimine 3a to give a) B(NMe2)3, and the bis-and tris(sulfonimino)boranes 10b and 11, b) B(NMe2)3 and the dithiatetrazadiborocine 15b. The diborylated sulfamide 6c (R2B = Ph2B) cannot be isolated. The synthesis of the monoborylated sulfonimines 9c, 9e and sulfonediimines 13, 14 is described.

Kristall-und Molekülstruktur von N,N'-Bis(1,3-dimethylbenzo[b]-1,3,2-diazaboroIidin-2-yl)carbodiimid

Abstract Crystals of the title compound (2) are monoclinic with a = 905.5(3), b = 593.6(2). c - 3243.5(8) pm, β = 95.63(2)°, Z = 4, space group P21/n. The molecule 2 neither has a C2-symmet-rical allene-type nor a D2d -symmetrical cumulene-type structure, but it has a non-linear B-N = C= N - B arrangement and is nearly planar. The central N = C= N angle has a value of 171.9(3)°, the B - N = C angles are 145.9(2)° and 163.1(3)°.

Diazaborolidyl - ein stabiler Substituent an Schwefel-Stickstoff-Verbindungen / Diazaborolidyl - a Stable Substituent at Sulfur Nitrogen Compounds

2-Chlor-diazaborolidine, [CH2-N(CH3)]2BC1 (5) and N-silylated sulfur nitrogen compounds with sulfur in the oxidation state + 4 or + 6 react to form the boranes 7-11 which are thermally stable compounds. Reactions with other chlorboranes like [(CH3)2N]2BC1, (6), (C6H5)2BCl or C6H5BCl2 as starting materials lead to less stable or unstable compounds. Spectroscopic data of the new compounds are given.

31P-NMR-Spektren von Phosphor(V)-nitrid-chloriden und Phosphor(V)-Schwefel(VI)-nitrid-chloriden / 31P NMR Spectra of Phosphorus (V)-nitride-chlorides and Phosphorus (V)-sulfur (VI)-nitride-chlorides

Preparation and properties of linear and branched phosphorus nitride chlorides with chlorosulfurylimide endgroups are described. The nmr spectra of phosphorus (V) nitride chlorides and phosphorus (V) sulfur (VI) nitride chlorides are compared and discussed. Chemical shifts δ31p and δ19F , structure of resonance signals and coupling constants are tabulated.

Ligandenaustauschreaktionen zwischen Halogenboranen und Alkylsilanen/Ligand Exchange Reactions between Haloboranes and Alkylsilanes

Abstract In a ligand exchange reaction between BHal3 (Hal = Cl, Br) and the tetraalkylsilanes Et4Si, (Me3Si)2CH2 or Ph2CHSiMe3 the alkylhaloboranes EtBBr2 or MeBHal2 and the alkylhalosilanes Et3SiBr, HalMe2Si-CH2-SiMe3, (HalMe2Si)2CH2, and Ph2CHSiMe2Br, respectively, are formed. Similarly, the methyloligosilanes (Me3Si)2 (1) and (Me3Si)2SiMe2 (2) react with BHal3 (Hal = Cl, Br, I) via methyl-halogen-transfer to give HalMe2Si-SiMe3 (Hal = Cl, Br, I), (HalMe2Si)2 (Hal = Br, I), HalMe2Si - SiMe2-SiMe3, (Me3Si)2SiMeHal, HalMe2Si - SiMeHal -SiMe3, (HalMe2Si)SiMe2 (Hal = Cl, Br) or (BrMe2Si)2SiMeBr besides MeBHal2 (Hal = Cl, Br, I) and Me2BI, respectively.