ZfN: Search Results

Browse byFacets

Bookbag ( 0 )

'Steric Effect' in keywords

Results 5 Items

1	Author	Werner Biffar, Heinrich Nöth	Requires cookie*
	Title	Beiträge zur Chemie des Bors
	Abstract	, 124 [1] Tris(trimethylsilyl)silyl-borane und Tris(trimethylsilyl)silyl-borate Contributions to the Chemistry of Boron, 124 [1] Tris(trimethylsilyl)silyl Boranes and Tris(trimethylsilyl)silyl Borates The reactions of several boron halides, methoxides, alkyls and hydrides with tris(tri-methylsilyl)silyllithium, which was isolated as the solvate [(CH3)3Si]3SiLi • SCtHsO, 1 (TMSSLi) have been studied. (CH 3)2B-Si[Si(CH 3) 3 ]3 and 9-[(CH 3)3Si] 3 Si-9-BBN, were isolated, while [(CH 3)3Si]3Si-B(«C4H 9)2 could only be detected by n B NMR. In addition TMSS-B[N(CH 3) 2 ]2, (TMSS) 2 BNMe 2 and (TMSS) 2 BOCH 3 were prepared. The methoxy-boranes (CHs)3_ n B(OCHa) n add to 1 forming silylborates; however, no OCH3/Si[Si(CH3)3]3 substitution occurs. The hydrogen bridge in 9-BBN is cleaved symmetrically. The results can be explained by the basicity and the steric requirements of the TMSS group. The TMSS group exhibits a deshielding effect at the boron nucleus relative to the (CH3)3Si group for silylboranes as well as for silylborates.
	Reference	Z. Naturforsch. 36b, 1509—1515 (1981); eingegangen am 3. Juli 1981
	Published	1981
	Keywords	Silylboranes, Silylborates, Steric effects, n B NMR Spectra
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/36/ZNB-1981-36b-1509.pdf
	Identifier	ZNB-1981-36b-1509
	Volume	36

2	Author	JanA K Du Plessis, Hans Rose, RobertA. Shaw	Requires cookie*
	Title
	Abstract	The synthesis of trimethylphosphazenyl -and triphenylphosphazenyl -fluorocy clotri -phosphazatrienes, N3P3F6-n(NPR3)n, by a silylation method using Me3SiNPR3 (R = Me or Ph) is reported. More phosphazenyl groups can be introduced if R = Me than if R = Ph. Isomers have been isolated, as have been mixed phosphazenyl derivatives, N3P3F6 -n-m (NPR3)N(NPR3') m (R = Ph, R' = Me). Substituted fluorophosphazenes,
	Reference	(Z. Naturforsch. 31b, 997—998 [1976]; received March 4/April 2 1976)
	Published	1976
	Keywords	Trimethylphosphazenylfluorocyclotri-phosphazatrienes, Triphenylphosphazenylfluorocyclotri-phosphazatrienes, Isomers, Silylation Method, Steric Effects
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/31/ZNB-1976-31b-0997_n.pdf
	Identifier	ZNB-1976-31b-0997_n
	Volume	31

3	Author	Hubert Schmidbaur, Stefan Schnatterer, KailashC. Dash, ArefA M Aly	Requires cookie*
	Title	Gold(I)-Bis(
	Abstract	diphenylphosphino)amid und einige Gold(I)-Bis(diarylphosphino)methanide mit sterisch anspruchsvollen Arylsubstituenten Gold(I)-bis(diphenylphosphino)amide and Some Gold(I)-bis(diarylphosphino)methanides with Bulkyl Aryl Substituents Intensely yellow coloured, insoluble gold(I)-bis(diarylphosphino)amides, [(CeH^P^NAu, 1, is obtained from lithiated bis(diphenylphosphino)amine and AuCl complexes of tertiary phosphines. 1 is assigned a dimeric eightmembered ring structure on the basis of its 197 Au-Mößbauer spectrum and of a direct analogy with the corresponding bis(phosphino)methanide complexes, whose structure has recently been confirmed by X-ray diffraction.
	Reference	(Z. Naturforsch. 38b, 62—66 [1983]; eingegangen am 16. September 1982)
	Published	1983
	Keywords	Gold Compounds, Metallocycles, Phosphino-amides, Phosphino-methanides, Steric Effects
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/38/ZNB-1983-38b-0062.pdf
	Identifier	ZNB-1983-38b-0062
	Volume	38

4	Author	Shinjiro Kobayashi3, W. Olfram Schnabelb	Requires cookie*
	Title	Reactions of Substituted Vinyl Cations in Acetonitrile Solution as Studied by Flash Photolysis, Part II
	Abstract	n 2 + Vinyl cations o f the structure ;C = C —R (I+) were generated by flash photolysis o f the R 1 2 1 corresponding halides. Lifetime measurements with the aid o f optical absorption measure ments yielded bimolecular rate constants k2 o f the reaction o f I+ with tetrahydrofuran and sev eral aliphatic alcohols. On the basis o f k2 values the steric effect o f various substituents R 1 and R2 at C2 and the combined mesomeric (+ M) and inductive (-1) effect o f substituent groups at C, on the electrophilicity o f I+ have been elucidated.
	Reference	Z. Naturforsch. 47b, 1319—1323 (1992); received March 9 1992
	Published	1992
	Keywords	Vinyl Bromide, Electrophilicity, Flash Photolysis, Substituent Effect, Steric Effect
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/47/ZNB-1992-47b-1319.pdf
	Identifier	ZNB-1992-47b-1319
	Volume	47

5	Author	G. Ar Zeller, Ette Schier, B. Ert, Schm Idbaur	Requires cookie*
	Title	The Crystal Structure of [Bis(tri-'butyl-phosphine)gold(I)] Chloride
	Abstract	The title compound is available from the reaction of labile gold(I) chloride com plexes and an excess of the ligand ('Bu3P), or from the N aBH 4 reduction of ('Bu3P)AuCl. It forms dark red cubic crystals, [a = 14.297(1) A at -5 6 °C, space group P2j3, Z = 4], with isolated chloride anions and [('Bu3P)2Au]+ cations of C3 symmetry, with linear two-coordinate gold centers.
	Reference	Z. Naturforsch. 49b, 1243—1246 (1994); received June 8 1994
	Published	1994
	Keywords	G old(I) Complexes, Phosphine Complexes, Gold(I) Coordination, Steric Effect, Crystal Structure
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/49/ZNB-1994-49b-1243.pdf
	Identifier	ZNB-1994-49b-1243
	Volume	49