Formation and Properties of Li2P7R (R = Si(CH3)3, CH3, C(CH3)3) The reaction of P7(Sime3)3 with Li3P7 in the molar ratio of 2:1 yields LiP7(Sime3)2, and in the molar ratio of 1:2 Li2P7Sime3 is formed. Li2P7me and Li2P7Cme3 (me = CH3) are obtained by reaction of white phosphorus with Lime, or LiCme3, respectively [2]. The compounds Li2P7R (R = Sime3, Cme3, me) show typical valence tautomerism, as established by 31P-n.m.r. spectroscopy at various temperatures. Also LiP(Sime3)2 transforms P7(Sime3)3 to yield Li2P7Sime3 but in this reaction considerable cleavage of P? P bonds occurs, too. 相似文献
Reactions of White Phosphorus with Lithium Alkyls The reaction of white phosphorus with Lime (me = CH3) (molar ratio P4: Lime = 1:1) in DME or THF via insoluble lithium polyphosphides yields Li3P7 1 , Li2P7me 2 and LiP7me2 3 , which react with me3SiCl or meBr to form P7(Sime3)3, P7(Sime3)2me and P7me3, respectively. All of these compounds were characterized by 31P-n.m.r. By higher amounts of Lime (molar ratio P4:Lime = 1:2) Li2P7me is decomposed. The analogous reaction of P4 with LiCme3 yields Li3P7, LiP7(Cme3)2, Li2P7Cme3, and additionally LiP4(Cme3)3 and LiP3(Cme3)2. Again insoluble lithium polyphosphides were observed as intermediates. Addition of me3SiCl to the reaction mixture affords P7(Sime3)3, P7(Sime3)2(Cme3), P7(Sime3)(Cme3)2 P4(Sime3)(Cme3)3, and P3(Sime3)(Cme3)2. In n-hexane/THF the reaction of P4 with LiCme3 in the molar ratio of 1:2 predominantly yields the fourmembered ring LiP4(Cme3)3 besides some of the three-membered ring LiP3(Cme3)2, which with me3SiCl yield P4(Sime3)(Cme3)3 and P3(Sime3)(Cme3)2. In addition to the mentioned main products are found: all compounds of the group P8(Sime3)5(Cme3) to P8(Sime3)(Cme3)5, the five-membered rings P5(Sime3)2(Cme3)3 and P5(Sime3)3(Cme3)2 as well as P(Sime3)2Cme3 and P(Sime3)3. 相似文献
Investigations Concerning the Metallation of the Cyclotetraphosphanes P4(Cme3)3(Sime3), P4(Cme3)2(Sime3)2, and P4(Sime3)4 The reaction of white phosphorus with LiCme3 and me3SiCl yields P4(Sime3)(Cme3)3 1 . With n-buLi this crystalline cyclotetraphosphane forms the crystalline LiP4(Cme3)3. In the same manner, n-buLi, with trans-P4(Sime3)2(Cme3)2 2 to yields LiP4(Sime3)(Cme3)2, which in contrast to LiP4(Cme3)3 decomposes within a few hours yielding P(Sime3)2n-bu 6 , P(Sime3)3 8 , LiP(Sime3)2 9 and also the cyclic compounds P4(Sime3)(Cme3)3 10 , LiP4(Cme3)3 11 and LiP3(Cme3)2 12 . The composition of the product mixture depends on the molar ratio of 2 to LiC4H9. At a molar ratio of 1:1 11 and 12 are not jet observed. At molar ratios of 1:1.5 and 1:2 P(Sime3)3 is not found. The amount of 11 and 12 grows with increasing concentration of n-buLi. On addition of n-buLi the solution of P4(Sime3)4 immediately turns red. Li3P7 and Li2P7(Sime3) (among others) are formed so fast that the first intermediates in the lithiation sequence so far could not be elucidated. These results demonstrate clearly that replacement of two me3Si groups in P4(Sime3)4 by two me3C groups excludes the rearrangement of LiP4(Sime3)(Cme3)2 to a P7-molecule. 相似文献
Crystal Structure of Dodecamethyl-hexasila-tetraphospha-adamantane (Sime2)6P4 Dodecamethyl-hexasila-tetraphospha-adamantane (Sime2)6P4 crystallizes in the cubic space group I 4 3m with a = 1081.7 pm and Z = 2 formula units. The bond lengths are P? Si = 224.9 pm, C? Si = 186.4 pm and C? H = 87 pm. The bond angles at the P-atoms are 104.4° and at the Si-atoms 118.8°. – The structure of the isotypic compound (Geme2)6P4 was refined. 相似文献
Preparation, Structures, and Properties of Tris-hexamethyl-trisila-tetraphospha-nortricyclene-bis-chromiumtricarbonyl [P4(Sime2)3]3[Cr(CO)3]2 Hexamethyl-trisila-tetraphospha-nortricyclene P4(Sime2)3 1 reacts with C6H6Cr(CO)3 or (CHT)Cr(CO)3 (CHT ? Cycloheptatriene) under formation of [P4(Sime2)3]3[Cr(CO)3]2 3 (red crystals), in which each of the Cr atoms is attached to one P atom of a P3 ring of the three molecules 1 . 3 can also be prepared by heating a solution of P4(Sime2)3Cr(CO)5 in benzene or THF up to 120–1307deg;C. The compound 3 crystallizes in an orthorhombic and a hexagonal form, the latter being stabilized by one mole toluene. As revealed by single crystal investigations, the symmetry ¯6, distances and angles are nearly unchanged. The o-form corresponds to a face centered cubic packing of the molecules, whereas the h-form is hexagonal close packed. 相似文献
Zusammenfassung Verbindungen des Typs R2NBCIN(Sime3)2* (R=C2H5,iC3H7, C6H11, C6H5) bleiben bis zu hohen Temperaturen beständig. Sie reagieren jedoch mit NaN(Sime3)2 unter Übertragung einer Methylgruppe von einem Silicium-zu einem Boratom zu N,N-Bis(trimethylsilyl)-tetramethylcyclodisildiazan und R2NBmeN(Sime3) (R=C2H5,iC3H7).
Compounds of the type R2NBClN(Sime3)2* were prepared. (R=C2H5,iC3H7, C6H11, C6H5. They do not show any tendency to condense thermally under elimination of trimethylchlorosilane. When these silylaminoboranes were allowed to react with NaN(Sime3)2, complicated rearrangements were observed. The compounds in which R=C2H5 oriC3H7 rearranged under formation of N,N-bis(trimethylsilyl)-tetramethylcyclodisildiazane and R2NBmeN(Sime)2. In this reaction a migration of a methyl group from silicon to boron occurs.
The Structures of the Heptahetero-Nortricyclenes P7(Sime3)3 and P4(Sime2)3 Tris(trimethylsilyl)heptaphospha-nortricyclene P7(Sime3)3 1 and Hexamethyl-trisila-tetraphospha-nortricyclene P4Si3me6 2 are structural analogons to the hetero-nortricyclenes P and P4S3. 1 crystallizes in the space group P21 with a = 965.7 pm, b = 1746.5 pm, c = 693.3 pm, β = 99.61° and Z = 2 formula units. In the P7 system tge P? P bond lengths differ functionally, namely 221.4 pm in the three-membered ring, 219.2 pm at the ring atoms and 217.9 pm at the bridgehead atom. The P? Si and Si? C bond lengths are 228.8 pm and 187.8 pm respectively. 2 crystallizes in the space group R3 with aR = 1129.3 pm, αR = 50.01° (hexagonal axes: a = 954.7 pm, c = 2956.9 pm) and Z = 2 formula units. In the P4Si3 systems the bond lengths are P? P = 220.2 pm, P? Si = 228.3 pm and 224.7 pm (to the bridgehead atom). The Si? C bond lengths are 187.3 pm. The structures are discussed with related compounds. 相似文献
Transition Metal Complexes of the Hexamethyl-trisila-tetraphospha-nortricyclene P4 (Sime 2) 3 P4(Sime2)3 1 reacts with Mo(CO)6, Cr(CO)5THF, and Mn(η-C5H5)(CO)2THF to give crystalline complexes in which 1 functions as a monodentate ligand. In each compound one phophorus atom of the cyclotriphosphane ring coordinates to the metal atom. Using Mn(η-C5H5)(CO)2THF, two different P atoms of the P3 Cr(CO)4 norbornadiene and 1 react, yielding the dimeric, red, crystalline compound (CO) 4Cr[μ-P4(Sime2)3]2Cr(CO)4. In this complex the two molecules of 1 are both bonded by two P atoms of the P 3 ring to the two Cr(CO)4 Units, forming a six-memered (CrP2)2ring. 相似文献
Formation of organosilicon compounds. 84. Synthesis and thermal rearrangement of some substituted linear and cyclic silanes In part IR we report on the synthesis of substituted silanes, and in part II on their thermal rearrangement. I: me3i--Sime3(me = CH3) is formed by dropwise addition of THF to a suspension of Li powder in me3SiCl; yield ～ 80%. The mixture me3Si--Sime2Cl, me3SiCl, Li powder and THF reacts analogously to form me2Si(Sime3)2; yield 80%. By the same type of reaction the following compounds are obtained: compound 1 from Brme2Si? CH2? Sime2Br, 1 from Brme2Si? CH2? Sime2Br, 2 from Brme2Si? Sime2? CH2? Sime2Br 16 and 3 from Bret2Si? CH2? CH2? Siet2Br (et = C2H5). 2 decomposes during its isolation from THF. 16 is formed from phme2Si? Sime2? CH2? Sime2ph 17 (ph = C6H5) by reaction with HBr, 17 either from phme2SiLi and Clme2SiCH2Cl or from phme2Si? Sime2Br and LiCH2? Sime2ph. II: me2Si(Sime3)2 rearranges at 440 °C (56 h) with insertion of the CH2 group (Si? H formation) into the Si? Si bond and the formation of me3Si? Sime2? CH2? Sime2H, me2HSi? CH2? Sime2? CH2? SiHme2, and me3Si? CH2? Sime? CH2? Sime2H. 1 reacts analogously. Methylated halogenated disilanes like Brme2Si? Sime2Br react with separation of: Sime2 and its insertion into the Si-halogen bond to form trisilanes. Different from both are the phenylated derivatives, though phme2Si? Sime2ph still forms phme2Si? Sime2? Sime2ph. 3 reacts with separation of C2H4, formation of the Si? H group and insertion of C2H4 into the Si? Si bond. 相似文献
me3Si? CCl2?Sime2Cl (me ? CH3) läßt sich mit n-buLi (bu ? C4H9) bei–100°C (Lösungsmittel THF/Äther) in me3Si? CCl(Li)? Sime2Cl a überführen. das mit meJ me3Si? CClme? Sime2Cl bildet. Wird a in Abwesenheit eines Abfangreagenzes langsam erwärmt, so bildet sich unter Abspaltung von LiCl (Cl aus der SiCl-Gruppe) über eine reaktive Zwischenstufe des Bicyclobutans b . Die Struktur von b ist durch NMR-Untersuchung, Röntgenstrukturanalyse und Abbaureaktionen gesichert. Mit HBr bzw. CH3OH werden die Si? C-Bindungen der Dreiringe in b gespalten, so daß sich me3Si? CH2? C(Sime2X)2Sime3 (X ? Br, OCH3) bildet. Formation of Organosilicon Compounds. 85. Formation, Reactions, and Structure of 1,1,3,3-Tetramethyl-2,4-bis(trimethylsilyl)-1,3-disilabicyclo[1, 1, 0]butane me3Si? CCl2? Sime2Cl (me ? CH3) with n-buLi (bu ? C4H9) at –100°C (solvent: THF/ether) yields me3Si? CCl(Li)? Sime2Cl a , which forms me3Si? CClme? Sime2Cl with meI. By warming a slowly in absence of any trapping reagent the bicyclobutane b is obtained via a reactive intermediate under elimination of LiCl (Cl from the SiCl group). The structure of b is established by nmr investigations, X-ray structure determination and chemical derivatisation. 相似文献
The Formation of Disilylphosphino-Element Compounds of C, Si, P The reactions of (me3Si)2PLi · OR2 a (OR2 = 1 monoglyme or 2 THF; me = CH3) with CH3Cl, CH2Cl2, ClCH2CH2Cl and ClCH2? C6H5 give the compounds (me3Si)2Pme, (me3Si)2P? CH2? P(Sime3)2, (me3Si)2P? CH2CH2Cl, (me3Si)2P? CH2CH2? P(Sime3)2 and (me3Si)2P? CH2C6H5 respectively. In the same manner a reacts with me2SiCl2 in a molar ratio 1:1 to (me3Si)2P? Sime2Cl and in a molar ratio 2:1 to (me3Si)2P? Sime2? P(Sime3)2 b . The compound b decomposes to [me3SiP? Sime2]2 and (me3Si)3P at 220°C. In the reactions of a with ClP(C6H5)2 and ClPme2 the compounds (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively, are obtained. a reacts with HgCl2 to (me3Si)2P? P(Sime3)2. (me3Si)3P can be cleaved with ClP(C6H5)2 and ClPme2 yielding (me3Si)2P? P(C6H5)2 and (me3Si)2P? Pme2, respectively. The 1H- and 31P-n.m.r. and mass spectroscopic data are reported. 相似文献
Formation of Organosilicon Compounds. 89. Selective Photobromination of Si-methylated Carbosilanes A selective photobromination of the C atoms in the skeleton of Si-methylated carbosilanes is reported. (me3Si? CH2)2Sime2 reacts to me3Si? CBr2? Sime2? CH2? Sime3 in good yields (me = CH3); the second CH2 group is considerably slower brominated. Photobromination of (me2Si? CH2)3 consecutively yields a and b . Also from (me2Si? CH2)4 the derivative with one CBr2 group is accessible. Bromination of tertiary CH groups is highly preferred; this is shown by the selective formation of c . The C-bromination of SiBr-substituted carbosilanes is significantly more difficult; nevertheless (Brme2Si)2CH2 selectively forms (Brme2Si)2CBr2. Brme2Si? CH2? Sime2? CH2? Sime3 forms Brme2Si? CH2? Sime2? CBr2? Sime3, i. e., only the CH2 group non-adjacent to SiBr is attacked. The formation of CHBr groups could not be detected. Higher temperatures and longer reaction times increase the formation of polymers. 相似文献
Formation of Organosilicon Compounds. 93. Investigations of the Mechanism of the AlBr3 Initiated Formation of Cyclic Carbosilanes. The mechanism of the formation of ringsystems in carbosilanes with AlBr3 is investigated using the deuterium compounds 1a and 3a . The number of deuterium atoms in the methyl groups of the reaction products shows at which points of the molecules the regrouping occurs under formation of the ringsystem. In the first initially the reaction of 1a yields D3C? Si(CH3)3 and 2a under separation of a CD3 group. The rearrangement forming 2a occurs at the marked Si? C-bonds (formula 1a ). No Al-organic intermediate compound is observed under cleavage of Si? C bond. Therefore the formation of ring-systems is based on the polarisation by the Lewis-acid AlBr3. Compound 3a reacts in an analogous way, what is shown by the isolation of Sime4 and 4a . The cleavage of the bonds is marked in formula 3a . The reaction of 8 forming 9 and (Sime3)2CH2 follows the same mechanism; it is investigated by 1H and 27Al-NMR spectroscopy. 相似文献
Reactions of [(me3Si)2P]2PLi with Chlorophosphanes [(me3Si)2P]2PLi 1 with (C6H5)2PCl yields only a small amount of the expected [(me3Si)2P]2P–P(C6H5)2 2 ; the main products are (me3Si)2P–P(C6H5)2 3 and (C6H5)2P–P(C6H5)2 4 besides some (me3Si)3P 5 and (C6H5)2P–Sime3 6. 3 and 4 result from the metallation of (C6H5)2PCl by 1 t-buPCl2 and 1 form the P3-ring (me3Si)(me3C)P3[P(Sime3)2] 9 as main product besides some [(me3Si)2P]2P–Sime3 7 and 5. 9 is afforded by elimination of me3SiCl, from the initially formed unstable [(me3Si)2P]2P–P(Cl)Cme3 10 . Similarly 1 and PCl3 yield mainly the P3-ring (me3Si)(Cl)P3 · [P(Sime3)2] 11 due to elimination of me3SiCl from [(me3Si)2P]2P–PCl2. 相似文献
Investigations Concerning the Reactivity of the Higher Silylphosphanes (me3Si)4P2, [(me3Si)2P]2PH, [(me3Si)2P]2P—Sime3, and (me3Si)3P7 The reaction of (me3Si)2P? P(Sime3)2 1 in ether solutions (THF, monoglyme) with t-buLi (me ? CH3; t-bu ? (CH3)3C) yields (me3Si)3P, (me3Si)2PLi and Li3P7 via (me3Si)2P? P(Li) (Sime3) 4 . Already at ?40° (me3Si)3P2Li 4 decomposes yielding (me3Si)2PLi, Li3P7 and (me3Si)3P. The metallation of (me3Si)3P2H with t-buLi leads to the same results. t-buLi with [(me3Si)2P]2PH 2 in pentane forms [(me3Si)2P]2PLi, which reacts on with meCl or me3SiCl to [(me3Si)2P]2Pme or [(me3Si)2P]2PSime3, resp. On addition of monoglyme to a suspension of [(me3Si)2P]2PLi in pentane, or by treating [(me3Si)2P]2PH in ethers with t-buLi (me3Si)2PLi, Li3P7, (me3Si)3P, are formed. The same compounds are generated by reacting [(me3Si)2P]2P—Sime3 in ethers with t-buLi. The metallation of (me3Si)3P7 in ethers with t-buLi yields (me3Si)2PLi, (me3Si)3P, (t-bu)3P4?(Sime3), Li3P7 and a red solid. The formation of (me3Si)2P7Li is the first step of this reaction. 相似文献
Formation of Organosilicon Compounds. LVI. Reactions of Si- and C-Chlorinated 1,3,5-Trisilapentanes with CH3MgCl (Cl3Si? CCl2)2SiCl2 (1) reacts with an excess of meMgCl (me = CH3) forming me3Si? C?C? Sime3 (2), Sime4, H2C?C(Sime3)[CH(Sime3)2] (3) as main products and (me3Si)2C? CH(Sime3) and as by-products. The cleavage reaction of (1) to (2) and (3) does not occur when the meMgCl-concentration is lowered. The reaction is started by the formation of a GRIGNARD reagent at a CCl-group in compound (1). Cl3Si? CCl2? SiCl2? CH2? SiCl3 forms with ; me3Si? CCl2? SiCl2? CHCl? SiCl3 forms (me3Si)2C?CH(Sime3). A reaction sequence is given. 相似文献
Niobium and Tantalum Complexes with P2 and P4 Ligands The photolysis of [Cp″Ta(CO)4] 1 (Cp″ = C5H3tBu2?1,3) and P4 affords Cp″(CO)2Ta(η4?P4) 2 , [{Cp″(CO)Ta}2(m??η2:2?P2)2] 3 and [Cp3″(CO)3Ta3(P2)2] 4 . In a photochemical reaction 2 and [Cp*Nb(CO)4] 5 form [{Cp*(CO)Nb}{Cp″(CO)Ta}(m??η2:2?P2)2] 6 and [{Cp*(CO)2Nb} {Cp*Nb}{Cp″(CO)Ta}(m?3?η2:1:1?P2)2] 7 , a compound with the novel m?3?η2:2:1?P2-coordination mode. The reaction of 2 and [Cp*Co(C2H4)2] 8 leads to [{Cp*Co} {Cp″(CO)Ta}(m??η2:2?P2)2] 9 , a heteronuclear complex with an ?early”? and a ?late”? transition metal. Complexes 2, 3, 7 and 9 have been further characterized by X-ray structure analyses. 相似文献
Formation of Organosilicon Compounds. LVIII. Synthesis of a Carbosilane with Propellane Structure 1 (· ? C resp. CH2; x ? Si(CH3)2 resp. Si) is formed by a coupling reaction of BrSi(CH2? Sime2? CH2? Sime2Br)3 2 with CCl4 and Li. The reaction of C6H5me2Si? CH2Li with Clme2Si? CH2Br leads to C6H5me2Si? CH2? Sime2? CH2Br. Metallation with lithium and succeeding reaction with Cl3SiC6H5 produces compound C6H5Si(CH2? Sime2? CH2? Sime2C6H5)3, which than forms 2 by cleavage with bromine. 相似文献
The synthesis of C6H5me2Si? CH2? Sime2? C?C? Sime2? CH2? Sime2C6H5 (a) is described, which forms Brme2Si? CH2? Sime2? C?C? Sime2? CH2-Sime2Br(b) with HBr. The reaction of (b) with HBr (1–4 moles at ?78°C) yields Brme2Si? CH2? Sime2Br, as well as 1,2-dibromo-ethane (main products) and Brme2Si? CH2/? Sime2CH = CHBr, Brme2Si? CH2? Sime2CH2? CHBr2. 相似文献
Formation of Organosilicon Compounds. 70. Reactions of Si-fluorinated 1,3,5-Trisilapentanes with CH3MgCl and LiCH3 F3Si? CCl2? SiF2? CH2? SiF3 3 reacts with meMgCl. (me = Ch3 starting with a Si-methylation and not with a C-metallation as in the corresponding Si- and C-chlorinated compounds, e. g. (Cl3Si? CCl2)2SiCl2 [2]. A CCl-hydrogenation is observed too, which in the case of F3Si? CCl2? SiF2? CHCl? SiF3 4 gives meS3Si? CCl2? Sime2? CH2? Sime3. (F3Si? CCl2)25 reacts with meMgCl to form preferentially 1,2-Disilapropanes by cleaving a Si? Cbond. The isolation of F3Si? CCl2H and meF2Si? CCl2? SiF2me allows to locate the bond where 5 is cleaved at the beginning of the reaction. With meLi 5 reacts to form mainly me3Si? C?C? Sime3, showing that in the reaction of meLi, being a stronger reagent than meMgCl, and 5 a C-metallation occurs, following the same mechanism as in the reaction with (Cl3Si? CCl2)2)SiCl2 [2]. The reaction conditions for the synthesis of Si-fluroinated and C-chlorinated 1,3,5-Trisilapentanes in a 0.1 mol scale are reported. N.m.r. data of all investigated compounds are tabulated. 相似文献
