Ulrich Wannagat

Darstellung und schwinkungsspektren von silylamiden der elemente zink, cadmium und quecksilber☆

Zusammenfassung Durch Reaktion von Natrium-bis(trimethylsilyl)amid mit ZnCl 2 , CdI 2 bzw. HgBr 2 bilden sich in hohen Ausbeuten die monomeren, leicht fluchtigen Silylamide [(CH 3 ) 3 Si] 2 NMN[Si(CH 3 ) 3 ] 2 (M = Zn, Cd, Hg). Ihie physikalischen und chemischen Eigenschaften werden mitgeteilt. Die aus den IR- und Raman-Spektren berechneten Kraftkonstanten sprechen in allen Verbindungen fur eine kovalente MN-Einfachbindung, hingegen im Einklang mit den 1 H-KMR-Spektren fur einen erhohten SiN-Bindungsgrad.

Silylamido-Verbindungen von Chrom, Mangan, Nickel und Kupfer

Natrium-bis-(trimethylsilyl)-amid reagiert mit CrCl3, MnJ2, NiJ2 und CuJ in Tetrahydrofuran zu fluchtigen, sehr hydrolyse-und sauerstoffempfindlichen Disilylamiden des Cr(III), Mn(II), Ni(II) und Cu(I).

Beiträgezur chemie der silicium-stickstoff-verbindungen: CVII. Darstellung, schwingungsspektren und normalkoordinatenanalyse von disilylamiden der 3. Gruppe: M[N(SiMe3)2]3 mit M = Al, Ga und In

Abstract The formerly unknown silylamides Ga[N(SiMe 3 ) 2 ] 3 (II) and In[N(SiMe 3 ) 2 ] 3 (III) as well as Al[N(SiMe 3 ) 2 ] 3 (I) were prepared in excellent yields from LiN(SiMe 3 ) 2 and the appropriate chlorides. Their thermal behaviour was investigated by thermal analysis. All compounds are monomeric, the central metal atoms possessing a trigonal environment. (II) is isostructural with (I) and the corresponding Fe and Cr compounds. The infrared and Raman spectra are almost identical for all compounds. A normal coordinate treatment suggests a close vibrational relationship of the MN(SiMe 3 ) 2 fragment with trisilylamines X 3 Si-N(SiMe 3 ) 2 . Good agreement of calculated and observed frequencies was achieved with the following MN stretching force constants: AlN 2.09, GaN 1.95, and InN 1.77 mdyn/A.

N-metallated silicon-nitrogen derivatives: preparation, structure and reactions

Ten years ago N-metallated silicon-nitrogen compounds were still unknown. Today the lithium as well as the sodium derivative of hexamethyldisilazane belong—second only to hexamethyldisilazane itself—to the most investigated of SiN-compounds. In 1959 we metallated for the first time the triorganylsilyl derivatives of ammonia and hydrazine with phenyllithium. The resulting N-substituted lithium compounds could be isolated. They were of interest to us primarily with respect to their transformation into multiple silylsubstituted derivatives of ammonia and of hydrazine. Later we noticed that they presented an extraordinary variety of preparative problems, and their physical properties turned out to be unusual and unpredictable. The more involved we became with the structure of these compounds the more enigmatic they seemed. Even today we can only describe many of them and explain little. In each new investigation they bring more surprising results, and the possibilities for their synthesis seem far from exhaustion. Well to the fore of interest are SiN-compounds substituted on the N-atom by alkali metals, and here again the doubly silylsubstituted amides have become the most important. It is not possible to prepare them by substitution of the H-atoms of the alkali amides. One must start with disilazanes and metallate them:

1,5-dihalogentrisilazane und ihre kondensation zu silicium-stickstoff-ringverbindungen

Zusammenfassung Cleavage of nonamethylcyclotrisilazane with dimethyldichlorosilane via eqn. (3) results in 1,3-dichloropentamethyldisilazane and 1,5-dichlorooctamethyl-trisilazane (I). HF in ether and NH 4 F respectively cleave hexamethylcyclotrisilazane via eqns. (5) or (6) into 1,5-difluorohexamethyltrisilazane (II). (I) reacts with water, ammonia, hydrazine or dilithiodimethylhydrazine forming the cyclotrisilazanes (III) and (V) the cyclotrisildiazoxane (IV) and the former unknown seven-membered SiN-ring system of the cyclotrisiltetrazane (VI).

Sila-Riechstoffe und Riechstoffisostere. - XII : Geruchsvergleiche homologer Organoelementverbindungen der vierten Hauptgruppe (C, Si, Ge, Sn)

Abstract Homologous compounds of the linalool type R(CH 3 ) 2 El-OH (with R = C 6 H 5 CH 2 and C 6 H 5 CH 2 CH 2 ) as well as their derivatives R(CH 3 ) 2 El-OCH 3 and [R(CH 3 ) 2 El] 2 O show, in dependence of El = C, Si, Ge and Sn partly similar, but sometimes very different characteristics of odor. Unexpected are high qualities of fragrance with El = Ge, whereas derivatives with El = Sn remain scentless, obviously owing to polymerization. Noteworthy are the strong differences of odor in the system C 6 H 5 CH 2 El(CH 3 ) 3 from C via Si and Ge up to Sn, standing fully contrary to the postulation of Amoore whereupon smell qualities are only controlled by size and shape of molecules. C 6 H 5 CH 2 Sn(CH 3 ) 2 OH (A1Sn) crystallizes as poly-μ-hydroxo-benzyldimethyltin with an one dimensional SnOSnO chain (SnO 2.17(9) and 2.29(9) A) in the monoclinic space group C 2 ( a = 12.696(4), b = 4.181(2), c = 10.626(3) A and β = 106.8(3)°).

Silylamido-Verbindungen des Vanadiums

Alkali-bis-(silyl)-amide NaN(SiR3)2 (R=CH3, O i C3H7) reagieren mit Isopropoxy-vanadium-oxidchloriden und mit VOCl3 unter Bildung von silylaminosubstituierten Vanadiumverbindungen. Isoliert wurden (R′O) n VO[N(SiR3)2]3−n (R′= i C3H7O,n=1 und 2) sowie

Sila-substituted perfumes: ???V. Sila derivatives of some musk scents

(R_3 Si)_2 N - - \begin{array}{*{20}c} \hfill {NSiR_3 } \\ \hfill {||} \\ \hfill V \\ \hfill | \\ \hfill {OSiR_3 } \\ \end{array} - - N(SiR_3 )_2 (R = = CH_3 )