Bildung siliciumorganischer Verbindungen. 105. Reaktionen des (Cl3Si)2CPMe2Cl mit Silylphosphanen

Formation of Organosilicon Compounds. 105. Reactions of (Cl₃Si)₂C?PMe₂Cl with Silylphosphanes The reaction of (Cl₃Si)₂C?PMe₂Cl 1 with MeP(SiMe₃)₂ proceeds at 130°C (15 hrs.), by cleavage of all Si? P bonds to compounds 2, 3, 4, 5 . The course of this reaction incorporates a number of stages of which the compounds (Cl₃Si)₂C? PMe₂? P(Me)SiMe₃, (Cl₃Si)₂C?PMe₂? PMe? P(Me)SiMe₃ and ClP(Me)SiMe₃ are important and are yet to be isolated. The reaction of (Cl₃Si)₂C?PMe₂Cl with LiP(SiMe₂)₂ produces compound 2 as well as p₂(SiMe₃)₄ and P(SiMe₃)₃. The formation of 2 can be explained by the initial formation of the intermediate (Cl₃Si)₂C?PMe₂? P(SiMe₂)₂ with reacts with 1 to produce 2 and (ClP(SiMe)₃)₂. The formation of P₂(SiMe₃)₄ is also explained by the reaction of ClP(SiMe₃)₂ with LiP(SiMe₃)₄. The reaction of (Cl₃Si)₂C?PMe₂C(H)PMe₂ at 130°C/15–20 hrs. is related to the formation of (Me₃Si)₂C(H)Pme₂ from corresponding Si-methylated phosphorylides with the exception that, at 0°C, this reaction goes to completion within a few minutes.     

Über Fluoride des zweiwertigen Eisens: Cs7Fe4F15

Concerning the Cleavage of Si? C Bonds in Si-methylated Carbosilanes The chances for the cleavage of Si? Me bonds (Me ? CH₃) and Si? C? Si bonds in their molecular skeletons using ICl or ICl/AlBr₃ are examined in 13 carbosilanes; i. e. (Me₂Si? CH₂)₃ 1 , 1,3,5,7-tetramethyl-1,3,5,7-tetrasilaadamantane 2 , (Me₃Si? CH₂)₂SiMe₂ 3 , HC(SiMe₃)₃ 4 , the 1,3,5,7-tetrasilaadamantane. carrying bhe ? CH₂? SiMe, group at one Si atom 5 , the 1,3,5-trisilacyclohexane, carrying the ? CH₂? SiNe₃ group 6 , three derivatives of the 1,3,5-trisilacyclohexane, carrying SiMe₃ groups at skeletal C atoms 7 , 8 , 9 , three derivatives of the 1,3,5-trisilacyclohexane, carrying CH₃, groups at skeletal C atoms 10 10, 11 , 12 and 13 , derived from (Me₂Si? CH₂)₃ having one ?CBr₂ group. Using ICl one Me group at each Si atom in 1 can be split off successively, finally yielding (ClMeSi? CH₂)₃. 2 is transformed to the Si-chlorinated 1,3,5,7-tetrasilaadamantane. 3 , treated with ICl yields (ClMeSi? CH₂)₂SiMeCl, as 4 forms HC(SiMe₂Cl)₃. Higher chlorinated compounds can be obtained by using ICl and AlBr₃ in catalytic amounts. Thus 1 leads to (Cl₂Si? CH₂)₃, no ring-opening is observed. However, in the reaction of 1 with HBr/AlBr₃ bromination at the Si atoms and ring-opening (ratio 1:1) proceed coincidently. The reaction of either 3 or (ClMe₂Si? CH₂)₂SiMeCl with ICl/AlBr₃ leads to (Cl₂MeSi? CH₂)₂SiCl₂, and (Me₃Si)₂CH₃ forms (Cl₂MeSi? )₂CH₂ similarly. The ? CH₂? SiMe₃ group in 5 and 6 is not cleaved off by ICl; the introduction of a Cl group at each Si atom is observed instead. Furthermore, 6 undergoes cleavage (≈8%) of the Si? C ring adjacent to the chain-substituted Si atom [formation of ClMe₂Si? (CH₂? SiMeCl)₂CH₂? SiMe₂? CH₂Cl]. 7 , 8 , 9 (having the ? SiMe₃ group at the C atoms) react with ICl by splitting off one Si? Me group from each Si atom. In 7 we also observe the ring-opening to an amount of ≈25% [formation of (ClMe₂Si)CH₂? SiMeCl? CH₂? SiMe₂? CH₂Cl]. In ₈ (having two CH(SiMe₃) groups the ring-opening reaction is reduced to about 5% [formation of ClMe₂? CH(SiMe₂Cl)? SiMeCl? CH(SiMe₂Cl)? SiMe₂? CH₂Cl], while in 9 (having three CH(SiMe₃) groups) it is not found at all. In 10 , 11 , 12 (having the CH₃ group at the C atoms) ICl substitutes one Me group (formation of SiCl) at each Si atom (no ring-opening). The CBr₂ group reduces the reactivity of 13 towards ICl. Only the split-off of one Me group at the Si atom in para-position to the CBr₂ group is observed. Using ICl/AlBr₃ higher chlorinated derivatives are obtained (no ring-opening). Most of the mentioned compounds were identified via their Si? H-containing derivatives, thus facilitating the chromatographic separation as well as the ¹H-NMR-spectroscopic investigations.     

Bildung siliciumorganischer Verbindungen. 83. Bildung,Reaktionen und Struktur von Yliden aus perchlorierten Carbosilanen

Formation of Organosilicon Compounds. 83. Formation, Reactions, and Structure of Ylides Generated from Perchlorinated Carbosilanes The CCl-moiety in perchlorinated carbosilanes as (Cl₃Si)₂ a, Cl₃Si? CH₂? SiCl₂? CCl₂? SiCl₃ b, (Cl₃Si? CCl₂)₂SiCl₂ c or (Cl₂Si? CCl₂)₃ d, e.g., cleaves the Si? P bond of me₃Si? Pme₂ e (me = CH₃); and by subsequent rearrangement ylides are formed. Such, treating e with a yields (Cl₃Si)₂CPme₂Cl 1, which also results from the reaction of me₂P? Pme₂ with a. The ylides also can be obtained by means of treating the carbosilanes a, b, c or d with LiPme₂. Thus, c with one mole of LiPme₂ yields Cl₃Si? CCl₂? SiCl₂? C(Pme₂Cl)? SiCl₃ or Cl₃Si? C(Pme₂Cl)? SiCl₂? C(Pme₂Cl)? SiCl₃, resp., with two moles of LiPme₂. The corresponding Si-methylated derivates do not form ylides; (me₃Si)₂CCl₂, e.g., with e in benzene yields me₃Si? CH(Pme₂)? Sime₃. One mole of Lime methylates 1 to yield (Cl₃Si)₂CPme₃ 11. With either LiPme₂, me₃Si? Pme₂ or Me₂P? Pme₂ 1 forms (Cl₃Si)₂CPme₂-Pme₂. Reacting 1 with CH₃OH/(C₂H₅)₂NH, (Cl₃Si)[SiCl₂(OCH₃)]CPme₂(OCH₃) is formed. Ylides also result from the reactions of partially C-chlorinated 1,1,3,3,5,5-hexachloro-1,3,5-trisilacyclohexanes with me₃Si? Pme₂, (Cl₂Si? CCl₂)₃ with three moles of me₃Si? Pme₂ or LiPme₂, resp., yields (Cl₂Si? CPme₂Cl)₃ 16, the 1,1,3,3,5,5-Hexachlor-2,4,6-tris(chlordimethylphosphoranyliden)-1,3,5-trisilacyclohexan, which crystallizes with one mole of monoglyme. X-ray structure determinations revealed that 1, 11 and 16 are planar. As well the (P? C) as the (Si? C) bond lengths are remarkably shortened; in 1 (P? C) to 173.3 pm, (Si? C) to 173.3 pm, (Si? C) to 179.5 pm, in 16 (P? C) to 168.7 pm, (Si? C) to 180 pm. The (Si? C) and (P? C) bond orders amount to about 1.33, and are relatively equally distributed. Therefore, the charge of the formal carbanion is equally distributed, which shall be expressed by means of the following kind of writing for 1 and 16 see “Inhaltsübersicht”.     

Bildung siliciumorganischer Verbindungen. XXXIX. Teilchlorierte Carbosilane

1. Photochlorination in CCl₄ of the Si-chlorinated carbosilanes (Cl₃Si? CH₂)₂SiCl₂ and (Cl₂Si? CH₂)₃ leads to totally chlorinated compounds, e. g. (Cl₃Si? CCl₂)₂SiCl₂. After chlorination has started at one CH₂ group, formation of a CCl₂ group is preferred before another CH₂ group is involved into the reaction. Thus preparation of compounds a, b, c is possible. Cl₃Si? CCl₂? SiCl₂? CH₂? SiCl₃ (a) for (b) and (c) (see “Inhaltsübersicht”). SO₂Cl₂ (benzoyl peroxide) as chlorinating agent reacts more slowly, and opens an access to carbosilanes containing CHCl groups such as (d), Cl₃Si-CHCl? SiCl₂? CH₂? SiCl₃ (e). Reactions of compounds (a) to (d) with LiAlH₄ yields carbosilanes with SiH groups, and partially chlorinated C atoms. 2. By the high reactivity of Si? CCl₂? Si groups an exchange of Cl atoms of CCl groups in perchlorinated carbosilanes is possible for H atoms of Si? H groups in perhydrogenated carbosilanes, thus allowing the preparation of compounds containing CHCl and SiHCl groups, e. g. according to Gl.(1) (Inhaltsübersicht). Further reactions, formulated as the last equations in Inhaltsübersicht, are reported as well as the rearrangement of H₃Si? CHCl? SiH₃.     

Synthese und Eigenschaften teilsilylierter Tri- und Tetraphosphane. Reaktionen lithiierter Diphosphane mit Chlorphosphanen

Synthesis and Properties of Partially Silylated Tri- and Tetraphosphanes. Reaction of Lithiated Diphosphanes with Chlorophosphanes The reactions of Li(Me₃Si)P? P(SiMe₃)(CMe₃) 1 , Li(Me₃Si)P? P(CMe₃)₂ 2 , and Li(Me₃C)P? P(SiMe₃)(CMe₃) 3 with the chlorophosphanes P(SiMe₃)(CMe₃)Cl, P(CMe₃)₂Cl, or P(CMe₃)Cl₂ generate the triphosphanes [(Me₃C)(Me₃Si)P]₂P(SiMe₃) 4 , (Me₃C)(Me₃Si)P? P(SiMe₃)? P(CMe₃)₂ 6 , [(Me₃C)₂P]₂P(SiMe₃) 7 , and (Me₃C)(Me₃Si)P? P(SiMe₃)? P(CMe₃)Cl 8 . The triphosphane (Me₃C)₂P? P(SiMe₃)? P(SiMe₃)₂ 5 is not obtainable as easily. The access to 5 starts by reacting PCl₃ with P(SiMe₃)(CMe₃)₂, forming (Me₃C)₂ P? PCl₂, which then with LiP(SiMe₃)₂ gives (Me₃C)₂ P? P(Cl)? P(SiMe₃)₂ 11 . Treating 11 with LiCMe₃ generates (Me₃C)₂P? P(H)? P(SiMe₃)₂ 16 , which can be lithiated by LiBu to give (Me₃C)₂P? P(Li)? P(SiMe₃)₂ 13 and after reacting with Me₃SiCl, finally yields 5 . 8 is stable at ?70°C and undergoes cyclization to P₃(SiMe₃)(CMe₃)₂ in the course of warming to ambient temperature, while Me₃SiCl is split off. 7 , reacting with MeOH, forms [(Me₃C)₂P]₂PH. (Me₃C)₂P? P(Li)? P(SiMe₃)₂ 18 , which can be obtained by the reaction of 5 with LiBu, decomposes forming (Me₃C)₂P? P(Li)(SiMe₃), P(SiMe₃)₃, and LiP(SiMe₃)₂, in contrast to either (Me₃C)₂P? P(Li)? P(SiMe₃)(CMe₃) 19 or [(Me₃C)₂P]₂PLi, which are stable in ether solutions. The Li phosphides 1 , 2 , and 3 with BrH₂C? CH₂Br form the n-tetraphosphanes (Me₃C)(Me₃Si)P? [P(SiMe₃)]₂? P(SiMe₃)(CMe₃) 23 , (Me₃C)₂P? [P(SiMe₃)]₂? P(CMe₃)₂ 24 , and (Me₃C)(Me₃Si)P? [P(CMe₃)]₂? P(SiMe₃)(CMe₃) 25 , respectively. Li(Me₃Si)P? P(SiMe₃)₂, likewise, generates (Me₃Si)₂P? [P(SiMe₃)]₂? P(SiMe₃)₂ 26 . Just as the n-triphosphanes 4 , 5 , 6 , and 7 , the n-tetraphosphanes 23 , 24 , and 25 can be isolated as crystalline compounds. 23 , treated with LiBu, does nor form any stable n-tetraphosphides, whereas 24 yields (Me₃C)₂P? P(Li)? P(SiMe₃)? P(CMe₃)₂, that is stable in ethers. With MeOH, 24 , forms crystals of (Me₃C)₂P? P(H)? P(SiMe₃)? P(CMe₃)₂.     

Bildung siliciumorganischer Verbindungen. 110. Reaktionen von (Cl3Si)2CCl2, seiner Si-methylierten Derivate,von (Cl3Si)2CHCl, (Cl3Si)2C(Cl)Me und Me2CCl2 mit Silicium (Cu-Kat.)

Formation of Organosilicon Compounds. 110. Reactions of (Cl₃Si)₂CCl₂ and its Si-methylated Derivatives as well as of (Cl₃Si)₂CHCl, (Cl₃Si)₂C(Cl)Me and Me₂CCl₂ with Silicon (Cu cat.) The reactions of (Cl₃Si)₂CCl₂ 1 , its Si-methylated derivatives (Me₃Si)₂CCl₂ 8 , Me₃Si? CCl₂? SiMe₂Cl 9 , (ClMe₂Si)₂CCl₂ 10 , Me₃Si? CCl₂? SiMeCl₂ 11 , Cl₂MeSi? CCl₂? SiCl₃ 12 as well as of (Cl₃Si)₂CHCl 38 , (Cl₃Si)₂CClMe 39 and of Me₂CCl₂ with Si (Cu cat.) in a fluid bed reactor ( 38 and 39 also in a stirred solid bedreactor) arc presented. While (Cl₃Si)₂CCl₂ 1 yields C(SiCl₃)₄ 2 the 1,1,3,3-tetrachloro-2,2,4,4-tetrakis(trichlorsilyl)-1,3-disilacyclobutane Si₆C₂Cl₁₆ 3 and the related C-spiro linked disilacyclobutanes Si₈C₃Cl₂₀ 4 , Si₁₀C₄Cl₂₄ 5 , Si₁₂C₅Cl₂₈ 6 , Si₁₄C₆Cl₃₂ 7 this type of compounds is not obtained starting from the Si-methylated derivatives 8, 9, 10, 11 They Produce a number of variously Si-chlorinated and -methylated tetrasila- and trisilamethanes. However, Cl₂MeSi? CCl₂? SiCl₃ 12 forms besides of Si-chlorinated trisilamethanes also the disilacyclobutanes Si₆C₂Cl₁₅Me 34 and cis- and trans Si₆C₂Cl₁₄Me₂ 35 as well as the spiro-linked disilacyclobutanes Si₈C₃Cl₁₉Me 36 , Si₈C₃Cl₁₈Me₂ 37 . (Cl₃Si)₂CHCl 38 mainly yields HC(SiCl₃)₃ 31 and also the disilacyclobutanes cis- and trans-(Cl₃Si)HC(SiCl₂)₂CH(SiCl₃) 41 and (Cl₃Si)₂C(SiCl₂)₂CH(SiCl₃) 45 the 1,3,5-trisilacyclohexane [Cl₃Si(H)C? SiCl₂]₃ 44 as well as [(Cl₃Si)₂CH]₂SiCl₂, and (Cl₃Si)₂CClMe 39 mainly yields (Cl₃Si)₂C?CH₂and (Cl₃Si)₂besides of HC(SiCl₃)₃, MeC(SiCl₃)₃and (Cl₃Si)₃C? SiCl₂Me.,. Me₂CCl₂ 59 mainly yields Me(Cl)C?CH₂, Me₂CHCl and HCl₂Si? CMe₂? SiCl₃, besides of Me₂C(SiCl₃)₂ and Me₂C(SiCl₂H)₂ Compound 3 crystallizes triclinically in the space group P1 (Nr. 2) mit a = 900,3, b = 914,0, c = 855,3 pm, α = 116,45°, β = 101,44°, γ = 95,86° and one molecule per unit cell. Compound 4 crystallizes monoclinically in thc space group C2/c (no. 15) with a = 3158.3,b = I 103.7, c = 2037.4 pm, β = 1 16.62° and 8 molecules pcr unit cell. The disilacyclobutane ring of compound 3 is plane, showing a mean distance of d (Si-C) =19 1.8 pm and the usual deformations of endocyclic angles: α_Si = 94,2°> 85,8° = α_C.The spiro-linked disilacyclobutane rings of compound 4 are slightly folded by a mean angle of (19.0°). Their mean distances were found to be d (Si? C) = 190.4 pm relating to the central carbon atom and 192.0 pm to the outer ones, respectively. The deformations of endocyclic angles: α_Si = 93,9°> 84,4° = α_C are comparable to those of compound 3.     

Bildung siliciumorganischer Verbindungen. LXII. Teilbromierte Carbosilane

Formation of Organosilicon Compounds. LXII. Partial Brominated Carbosilanes The photobromination of 1 leads to compound 2 as well as to C-chlorinated derivatives if the time of reaction is prolonged. Compound 2 is also formed from (Br₂Si–CH₂)₃; Gl. (1) see ?Inhaltsübersicht”?. In a corresponding reaction (Cl₃Si–CH₂)₂SiCl₂ gives successively Cl₃Si–CHBr–SiCl₂–CH₂–SiCl₃, Cl₃Si–CBr₂–SiCl₂–CH₂–SiCl₃ and Cl₃Si–CCl₂–SiCl₂–CH₂–SiCl₃. (Cl₃Si)₂CBr₂ is accessible through the photobromination of (Cl₃Si)₂CH₂. The reactivity of the CBr₂-group is quite obvious in the reaction of Cl₂Si–CBr₂–SiCl₂–CH₂–SiCl₃ with LiAlH₄ yielding (H₃Si–CH₂)₂SiCl₂ as well as in the reaction of compound 2 with CH₃MgCl yielding [(CH₃)₂Si–CH₂]₃. By treatment of the SiH groups with bromine the preparation of compounds with the general formulas CH₃SiH_nBr_3?n; (H_3?nSiBr_n)₂CH₂; (H_3?nSiBr_n? CH₂)₂SiH_2?nBr_n; (H_2?nBr_nSi? CH₂)₃ and (H_3?nSiBr_n)₂CCl₂ is possible. Analysis of the nmr spectra shows that 1,3-Dibromo-1,3,5-trisilacyclohexane is formed to 67% in the trans and to 33% in the cis configuration; 1,3,5-Tribromo-1,3,5-trisilacyclohexane is formed to 80–90% in teh cis-trans configuration. The results of ¹H and ²⁹Si NMR investigations are reported.     

Über Trichlorphosphazo-Verbindungen aus Nitrilen. III. Die Reaktion zwischen Acrylnitril und PCl3

On Trichlorophosphazo Compounds from Nitriles. III. The Reaction between Acrylonitrile and PCl₃. The reaction of PCl₃ with acrylonitrile at higher temperatures gives CH₂Cl? CCl₂? CCl₂? N? PCl₃ ( II ). On pyrolysis of (II), CH₂Cl? CCl₂? CN (IV) is form- ed. Treatment of (II) with SO, results in CHzCL? CCl₂? CCl?N-P(0)Cl₂ ( III ). At lower temperatures and/or in the presence of PCl₃, acrylonitrile reacts with PCl₃ to give the cis/ trans isomers VIa and VIb .     

Zur Bildung cyclischer Silylphosphane Umsetzung von Li-Phosphiden mit R2SiCl2 (R = Me,Et, t-Bu)

Formation of Cyclic Silylphosphanes. Reaction of Li-Phosphides with R₂SiCl₂ (R? Me, Et, t-Bu) The reaction of Me₂SiCl₂ with Li-phosphides (mixture of LiPH₂, Li₂PH) leads to the formation of Me₂Si(PH₂)Cl 1 , Me₂Si(PH₂)₂ 2 , H₂P? SiMe₂? PH? SiMe₂Cl 3 , (H₂P? SiMe₂)₂PH 4 , (HP? SiMe₂)₃ 6 , 5 , 7 , 8 , 9 , 10 , 40 . Excess of phosphides in Et₂O – as well as excess of LiPH₂ – favourably forms 10 . Li₂PH (virtually free of Li₃P and LiPH₂) is obtained by reaction of LiPH₂ · DME with LiBu; Li₃P by reaction of PH₃ with LiBu in toluene. Isomerization by Li/H migration determines the course of reaction of the PH-bearing compounds with Li-phosphides. With Me₂SiCl₂ Li₃P mainly generates compound 10 . The reaction of the Li-phosphides with Et₂SiCl₂ mainly leads to (HP? SiEt₂)₃ 18 and (HP? SiEt₂)₂ 17 as well as to Et₂Si(PH₂)Cl 11 , Et₂Si(PH₂)₂ 12 , (ClEt₂Si)₂PH 13 , H₂P? SiEt₂? PH? SiEt₂Cl 14 , (H₂P? SiEt₂)₂PH 15 and 16 . In the reaction with LiPH₂ · DME the same compounds are obtained and isomerization by Li/H migration (formation of PH₃) already begins at ?70°C. In toluene ClEt₂Si? P(SiEt₂)₂P? SiEt₂Cl is additionally formed. Derivatives of 9, 10, 40 are not observed. The reaction of (t-Bu)₂SiCl₂ with LiPH₂ leads to HP[Si(t-Bu)₂]₂PH 20 (yield 76%) and formation of PH₃, the reaction with Li₂PH to 20 (54%) besides HP[Si(t-Bu)₂]₂PLi 21 .     

Bildung siliciumorganischer Verbindungen. 97. Über den Einfluß der Si-Substituenten (Me,Cl) auf Bildung und Reaktion von Yliden

Formation of Organosilicon Compounds. 97. About the Influence of the Si-Substituents (Me, Cl) upon the Formation and the Reactions of Ylides 1,3-disilapropanes with different grade of chlorination or methylation at the silicon atoms and containing a CCl₂ group cleave the Si? P bond of Me₃SiPMe₂. By subsequent rearrangement ylides with ? PMe₂Cl group are formed. The reactivity of the CCl₂ group depends on the grade of Si-chlorination resp. Si-methylation. Si-methylation decreases the reactivity of the CCl₂ group. The reaction of 1,3-disilapropanes and Me₃SiPMe₂ (molar ratio 1:1) runs in a sequence shown in “Inhaltsübersicht”. Ylid C is able either to react with the initial compound A forming B, or in competition decomposes forming D. Reacting Si-perchlorinated carbosilanes, the decomposition forming D is not to be observed. In Si-methylated ylides like (Me₃Si)₂C?PMe₂? PMe₂ and (Me₃Si)₂C?PMe₂? P(Me)SiMe₃ the ylid carbon atom is able to abstract a proton of the P? CH₃ group resp. P? H groups of the trivalent phosphorus forming (Me₃Si)₂C(H)PMe₂. The rearrangement is proved by deuterated derivatives. The different behaviour is due to the increased basicity of the ylid-C atom in Si-methylated phosphorus ylides. Quite the same behaviour show the phosphorus ylides of 1,3,5-trisilacyclohexane.     

Zur Kenntnis des Aluminiumchlorids. Die Umsetzung von AlCl3 mit PCl5 und Methylamin

Aluminium trichloride forms the adducts AlCl₃ · NH₂CH₃, AlCl₃ · 2NH₂CH₃, AlCl₃ · 4NH₂CH₃; AlCl₃ · NH₃CH₃Cl, AlCl₃ · 2NH₃CH₃Cl. The interaction between AlCl₃, PCl₅ and NH₃CH₃Cl in the molar ratio 1:3:2 proceeds according to the reaction equation in “Inhaltsübersicht”. On applying other stoichiometric amounts, [Cl₂(NHCH₃)P? N(CH₃)? AlCl₃] · HCl and [Cl₃P? N(CH₃)? AlCl₃] · HCl are obtained; the latter reacts as [Cl₃P? NHCH₃][AlCl₄]. At the molar ratio AlCl₃:PCl₅:NH₃CH₃Cl = 1:2:4 a compound is formed being presumably the six-membered heterocycle formulated in “Inhaltsübersicht”. With [Cl₃P?N? PCl₃] and aluminium chloride [Cl₃P?N? PCl₃][AlCl₄] is formed.     

Alternativ-Liganden. XXII. Rhodium(I)-Komplexe mit Donor/Akzeptor-Liganden des Typs Me2PCH2CH2SiXnMe3−(X = F,Cl, OMe)

Alternative Ligands. XXII. Rhodium(I) complexes with Donor/Acceptor Ligands of the Typs Me₂PCH₂CH₂SiX_nMe_3?n(X = F, Cl, OMe) Donor/acceptor ligand of the type Me₂PCH₂SiX_nMe_3?n react with [Rh(CO)₂Cl]₂ ( 1 ) to give the mononuclear complexes RhCl(CO)(PMe₂CH₂CH₂SiX_nMe_3?n)₂ ( 2-6 , Table 1) with planar geometry of the donor atoms, one exception being Me₂PCH₂CH₂CH₂SiCl₃, yielding the crystalline Rh^III-complex RhCl₂(CO)(PMe₂CH₂CH₂SiCl₂)(PMe₂CH₂CH₂SiCl₃) ( 7 ) by oxidative addition of one of the SiCl bonds to the Rh¹ precursor. Structures with Rh → Si interaction between the basic central atoms and the acceptor group SiX_nMe_3?n could be detected in the isolated products neither spectroscopically nor by X-ray diffraction of the two representatives RhCl(CO)(PMe₂CH₂CH₂SiF₃)₂ ( 2 ) and RhCl(CO)[PMe₂CH₂CH₂siF₃]₂ ( 2 ) and RhCl(CO) [PMe₂CH₂CH₂Si(OMe₃]₂ ( 6 ). The presence of such acid/base adducts in the reaction mixture is indicated for the more acidic acceptor groups SiX_nMe_3?n byv_co values near 1990cm^?1, (see Table 3). The complex RhCl(CO)PMe₃)(PMe₂CH₂CH₂SiF₃ ( 8 ) is obtained by the reaction of RhCl(CO)(PMe₃)₂ ( 9 ) with Me₂PCH₂SiF₃ and has been identified spectroscopically in a mixture with 2 and 9 .     

Zur Kenntnis der Chemie der Silazane. IV. Über ein Sulfurylphosphazo-silazan

Trichlorophosphazo-sulphurylchloride. Cl₃P?N? SO₂Cl, reacts with heptamethyldisilazane to yield the Si? N? P compound (I) formulated in ?Inhaltsübersicht”?. (I) reacts with PCl₅ or C₆H₅? PCl₄ forming the known 2,2,2,4,4,4-hexachloro-1,3-di-methylcyclo-diphosphazane(II), accompanied by the compound Cl₃P?N? SO₂Cl and C₆H₅? PCl₂?N? SO₂Cl, respectively, which were detected by means of ³¹P-NMR spectroscopy.     

Preparation of bis-(γ-trifluoropropyl)dichloro

Summary It was shown that (CF₃CH₂CH₂)₂SiCl₂, along with Cl₃SiCH₂CH₂CF₃ and CH₃Si(Cl)₂CH₂CH₂CF₃ may easily be prepared without danger by the addition of H₂SiCl₂ and HSiCl₃ or CH₂SiHCl₂ in the presence of platinohydrochloric acid.     

Bildung siliciumorganischer Verbindungen. XXXVIII. Umsetzung perchlorierter Carbosilane mit LiAlH4

By LiAlH₄ (Cl₃Si)₂CH₂, (Cl₂Si? CH₂)₂SiCl₂ are reduced to (H₃Si)₂CH₂ (a), (H₃Si? CH₂)₂SiH₂ (b) and (H₂Si? CH₂)₃(c). However with the compounds (Cl₃Si)₂CCl₂, (Cl₃Si? CCl₂0₂SiCl₂ and (Cl₂Si? CCl₂)₃ cleavages of the Si? C-bond and reduction of the CCl-groups occur apart from the normal reduction of the Si-Cl-groups to (H₃Si)₂CCl₂ (d), (H₃SiCCl₂)₂SiH₂ (e) and (H₂Si? CCl₂)₃. Excess LiAlH₄ favours this cleavage, the exact amount of a quarter of a mole LiAlH₄ per SiCl-group allows the formation of (d), (e), (f). The cleavage of (e) is in accordance with: (1), (2),(3). Therefore SiH₃₄ and (H₃Si)₂CCl₂ are the main-reaction-products and CH₃SiH₃ is formed acc. to equ. (3). Because of the cleavage of (H₂Si? CCl₂)₃ with LiAlH₄ H₃Si? CCl₂? SiH₂? CH₃and H₃Si? CH₂? SiH₂? CH₂? SiH₂? CH₃ are preferentially formed after the hydrolysis. The CH₂-containing compounds (a), (b), (c) cannot be cleaved in an analogous reaction.     

Bildung siliciumorganischer Verbindungen. LVI. Reaktionen Si- und C-chlorierter 1,3,5-Trisilapentane mit CH3MgCl

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.     

Bildung siliciumorganischer Verbindungen. 70 [1]. Reaktionen Si-fluorierter 1,3,5-Trisilapentane mit CH3MgCl und LiCH3

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)_{2 5} 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.     

Bildung und Struktur des iso-Tetraphosphans P[P(SiMe3)Me]3

Formation and Structure of iso-Tetraphosphane P[P(SiMe₃)Me]₃ The reaction of MeP(SiMe₃)₂ with PCl₃ (molar ratio 3:1, ?78°C, n-pentane) yields by cleaving of the P? Si bond P[P(SiMe₃)Me]₃ 1 with Cl₂P? P(SiMe₃)Me and ClP[P(SiMe₃)Me]₂ as intermediates. The reaction rate decreases by the increase of phosphorylation. The last reaction step (formation of 1 ) occurs while warming up to room temperature. 1 forms colorless hexagonal crystals, melting point 65 ± 1°C. Tris(trimethylsilyl-methyl-phosphino)phosphane 1 crystallizes monoclinically in the space group Cc (No. 8) with Z = 8 formula units per unit cell. The molecules possess approximated C₃ symmetry and have (RRR) and (SSS) configurations, respectively. The bond distances d?(P? P) = 220.1 pm, d?(P? C) = 186.5 pm, and d?(P? Si) = 225.2 pm are normal and within the expected range of known distances. According to repulsive interactions between the non bonded electron pairs of the terminal P atoms and the protons of the methyl groups the angles at the central and terminal P atoms are enlarged to ? P P P = 105.1° and ? P P C = 106.9°, respectively.     

Bildung siliciumorganischer Verbindungen. XXXXVI. Si-fluorierte Carbosilane

Formation of organosilicon compounds. XXXXVI. Si-fluorinated carbosilanes Compounds (1)–(7) (see “Inhaltsübersicht”) are obtained by reaction of carbosilanes containing Si? Cl groups with ZnF₂. The linear compounds (8) and (9) are prepared from ZnF₂ and (Cl₃Si)₂CCl₂, and (Cl₃Si? CCl₂)SiCl₂, respectively, whereas the cyclic compounds are formed by photochemical chlorination. Photochemical chlorination of (3) goes via compounds (13) and (14) (isolation is possible); both of them can be prepared too by reaction of Si? Cl derivatives with ZnF₂. Compounds (16) and (17) are obtained from the corresponding Si? Cl derivatives.     

Zur Bildung von Disilylphosphino-Element-Verbindungen des C,Si, P

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.