Lithium hydrazines, crystal structures

Summary Fluorosilylamines and -hydrazines react with organolithium compounds to yield stable lithium derivatives. Perfluoro (Si-N) four- and six-membered ring systems are obtained with SiF4. The synthesis and crystal structures of the compounds are discussed. 

Four crystal structures of lithiated bis(silyl)hydrazines are described.16,32-35 The Li centers exhibit tri- and tetracoordination, but because of Li-C interactions, the Li atoms may also adopt higher coordination numbers. All lithiated bis(silyl)hydrazines show side-on and end-on coordinated lithium. 

Only the lithium salt of a tris(trimethylsilyl)hydrazine 76 is described.35,40 It crystallizes as a dimer via a Li—N bond in a ladder structure, forming a tricyclic system with one (LiN)2 four-membered ring and two LiN2 three-... 

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