Bis(trimethylsilyl)-phosphaethene und Tris(trimethylsilyl)silyl-fluorphosphane

Abstract

<jats:title>Abstract</jats:title><jats:p> Phosphaethenes of the type (Me<jats:sub>3</jats:sub>Si)<jats:sub>2</jats:sub>C = P -NRSiMe<jats:sub>3</jats:sub> R = C<jats:sub>10</jats:sub>H<jats:sub>15</jats:sub> (7), CMe<jats:sub>3</jats:sub> (8), 2.4.6-Me<jats:sub>3</jats:sub>C<jats:sub>6</jats:sub>H<jats:sub>2</jats:sub> (10)), LiF, and Me<jats:sub>3</jats:sub>SiF are obtained in the reaction of the aminodifluorophosphanes (3-5) with the lithium salt of tris(trimethylsilyl)methane (1). 10 is isolated as by-product. The main product is F<jats:sub>2</jats:sub>PC(SiMe<jats:sub>3</jats:sub>)<jats:sub>3</jats:sub> (9). The lithium salt of tris(trimethylsilyl)silan (2) reacts with 3 -6 to give the thermally stable substitution compounds (Me<jats:sub>3</jats:sub>Si)<jats:sub>3</jats:sub>Si -PF-NRSiMe<jats:sub>3</jats:sub> (11-14). The fluorosilylphosphane Me<jats:sub>3</jats:sub>Si(CMe<jats:sub>3</jats:sub>)P -SiFMe - N(SiMe<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub> (15) is formed in the reaction of Me<jats:sub>3</jats:sub>Si(CMe<jats:sub>3</jats:sub>)PLi and F<jats:sub>2</jats:sub>SiMeN (SiMe<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub>.</jats:p>

Silylphosphanes: Developments in Phosphorus Chemistry

“…Thermal treatment of the lithium salt t Bu 2 (F)Si−P[Li(THF) 3 ] t Bu ( 350 ) (see (116)), the crystal structure of which has been determined by a X-ray-structure analysis,290a leads to the four-membered ring [ t Bu 2 Si−P t Bu] 2 ( 325i ) 290b via the phosphasilene t Bu 2 SiP t Bu. It could not be isolated, but was monitored by 31 P NMR data 290a…”

P‐Aminophosphaalkenes with C‐Isopropyldimethylsilyl Groups

“…The established methods for the transformation of P ‐halogenophosphaalkenes (Me 3 Si) 2 C=PCl and Me 3 Si(Ph)C=PBr into P ‐aminophosphalkenes are (i) triethylamine‐supported P–N bond formation with primary amines or with bis(trimethylsilyl)amine, (ii) reactions with metallated amines with metal halide precipitation, and (iii) transamination with trimethylsilylamines . The amination reactions with ( i PrMe 2 Si) 2 C=PCl ( 1 ) as a starting material are collected in Scheme , including the compounds 5 , 6 , 12 , and 13 , which have already been reported in the context of iminobisphosphaalkene syntheses.…”

“…P ‐Aminophosphalkenes (Me 3 Si) 2 C=PN RR ′ and Ph(Me 3 Si)C=PN RR ′ have been known for three decades, whereas attempts to extend recent studies on heteroatom‐bridged bisphosphaalkenes [(Me 3 Si) 2 C=P] 2 E ( E = O, S, Se, Te, PR, As R , Sb R ) to imino‐bridged bis‐phosphaalkenes [(Me 3 Si) 2 C=P] 2 N R revealed the instability of these heteropentadienes (Scheme , R = Me 3 Si, top), which undergo thermodynamically favorable intramolecular cyclization reactions. [6a], [6b]…”

The tris(trimethylsilyl)silyl group in organic, coordination and organometallic chemistry

“…The majority of reactions of lithium hypersilanide with phosphorus chlorides are accompanied by the formation of (Me 3 Si) 3 SiCl (which is thermodynamically a very favourable product), and poly-or oligophosphines. 123 ± 126 The complex of lithium tris(trimethylsilyl)silanide with THF (5) reacts with aminodifluorophosphines to give thermally stable derivatives 32a ± d. 127 Heating or distillation of compounds 32a ± d does not result in the elimination of Me 3 SiF, whereas related tris(trimethylsilyl)methyl derivatives are unstable and are readily converted into ylides (Me 3 Si) 2 C=PN(R)SiMe 3 (R = Bu t , 2-adamantyl) upon elimination of fluorotrimethylsilane. 127 The reaction of TTS-Li with 1-chloro-1H-phosphyrene 33 yielded the TTS-derivative 34, which is relatively stable at 20 8C, but decomposes in light.…”

“…123 ± 126 The complex of lithium tris(trimethylsilyl)silanide with THF (5) reacts with aminodifluorophosphines to give thermally stable derivatives 32a ± d. 127 Heating or distillation of compounds 32a ± d does not result in the elimination of Me 3 SiF, whereas related tris(trimethylsilyl)methyl derivatives are unstable and are readily converted into ylides (Me 3 Si) 2 C=PN(R)SiMe 3 (R = Bu t , 2-adamantyl) upon elimination of fluorotrimethylsilane. 127 The reaction of TTS-Li with 1-chloro-1H-phosphyrene 33 yielded the TTS-derivative 34, which is relatively stable at 20 8C, but decomposes in light. 128 Sodium-potassium phosphide prepared from white or red phosphorus and a Na/K alloy reacts with chloro tris(trimethylsilyl)silane to give [(Me 3 Si) 3 Si] 3 P 7 (35), a colourless crystalline compound in which the nortricyclane cell P 7 contains three TTS substituents.…”