Jump to Main Content
Cyclische Silylhydrazine - Kristallstrukturen isomerer fünf- und sechsgliedriger Ringe / Cyclic Silylhydrazines - Crystal Structures of Isomeric Five- and Six-Membered Rings
- Gellermann, Eike, Klingebiel, Uwe, Witte-Abel, Henning, Schäfer, Martina
- Zeitschrift für Naturforschung 2014 v.55 no.6 pp. 504-510
- crystal structure, hydrazides, hydrazines, lithium
- The lithium derivative of di(isopropyl)aminofluorosilylhydrazine cyclizes with formation of a five-membered silylhydrazine ring system (1). The analogous reaction of di(tert-butyl)- fluorosilylhydrazine gives the six-membered silylhydrazine ring system (2). 1 isomerizes thermally to the six-membered cyclic silylhydrazine 3. LiF-elimination from lithiated (Me₃C)₂₋ SiFNHNHSiF(CHMe₂)₂ leads to the formation of the six-membered cyclic silylhydrazine 4, [(Me₂HC)₂Si-NH-NSiF(CMe₃)₂]₂. Symmetrical six-membered tetra(fluoro)silylhydrazine rings, (F₂SiNRNR)₂ (5: R = SiMe₃, 6: R = SiMe₂CMe₃) are obtained in the reaction of bis(trifluorosilyl)hydrazines with dilithium-bis(silyl)hydrazides, whereas a five-membered unsymmetrical silylhydrazine (7: (RNSiF₂)₂N-NR'₂, R = SiMe₂CMe₃, R′ = SiMe₃) is formed in the reaction of R(SiF₃)N-N(SiF₃)R and R'(Li)N-N(Li)R'. In the reaction of the same fluorosilylhydrazine with dilithiated N,N'-diphenylhydrazide the unsymmetrical six-membered ring 8 is obtained. The crystal structures of 1, 2 and 3 are reported.