30006-66-7

Upstream product

• 75-77-4 chloro-trimethyl-silane 
• 80431-36-3 2,2-Dimethyl-4,4-diphenyl-1,3,3-tris(trimethylsilyl)-1-aza-2-silacyclobutan 
• 119-61-9 benzophenone 
• 66239-87-0 4,4-Dimethyl-3-(trimethylsilyl)-5,5-bis(trimethylsilyl)-1,2,3-triaza-4-sila-1-cyclopenten 
• 13686-33-4 t-butyl azide 
• 108148-61-4 4,4-Dimethyl-3-(triphenylsilyl)-5,5-bis(trimethylsilyl)-1,2,3-triaza-4-sila-1-cyclopenten 
• 4648-54-8 trimethylsilylazide 
• 108148-86-3 4,4-Dimethyl-3-p-tolyl-5,5-bis(trimethylsilyl)-1,2,3-triaza-4-sila-1-cyclopenten 
• 80431-43-2 2,2-Dimethyl-4,4-diphenyl-3,3-bis(trimethylsilyl)-1-oxa-2-silacyclobutan 
• 69322-38-9 tri-t-butylsilyl azide 
• 103457-88-1 azido(di-tert-butyl)(methyl)silane 
• 117984-08-4 Brom(fluordiphenylsilyl)bis(trimethylsilyl)methan 
• 117984-10-8 Brom(bromdiphenylsilyl)bis(trimethylsilyl)methan 
• 18107-18-1 diazomethyl-trimethyl-silane 

Downstream Products

• 1402147-93-6 N,N-bis(trimethylsilyl)aminotrimethylsilylisonitrilium tetrakis(pentafluorophenyl)borate 
• 1402147-98-1 N,N-bis(trimethylsilyl)aminoisonitrile tris(pentafluorophenyl)borane 
• 85332-21-4 (3-phenylpropa-1,2-diene-1,1-diyl)bis(trimethylsilane) 

Relevant academic research and scientific papers

Tetrakis(trimethylsilyl)tetrahedrane

Tetrakis(trimethylsilyl)tetrahedrane 3 has been synthesized upon irradiation of tetrakis(trimethylsilyl)cyclobutadiene 8, which can be prepared either by thermal nitrogen elimination from trimethylsilyl-[1,2,3-tris(trimethylsilyl)-2-cycloprop-l-enyl] diaz

Reactivity of the Silaethene Ph2Si=C(SiMe3)2

Silaethene Ph2Si=C(SiMe3)2 (3), generated as a reaction intermediate by the thermal elimination of LiX from Ph2SiX-CLi(SiMe3)2 (X = Br, F) or by the thermal cycloreversion of the cycloadduct of 3 and Ph2C=NSiMe3, forms adducts 3*donor, the stability of which increases in the order of donor = Et2O according to an ene reaction, with a=b (e.g.CH2=CHOMe; Ph2C=NSiMe3) or a=b=c (e.g. (t-Bu)2RSiN3, R = Me, t-Bu) or a=b-c=d with or or cycloaddition.The following order of relative reactivity of trapping reagents for Ph2Si=C(SiMe3)2 was found: Ph2CO > (t-Bu)2MeSiN3 > butadiene > 2,3-dimethylbutadiene > Ph2CNSiMe3 > (t-Bu)3SiN3 > anthracene.Summing up, it may be said that going from Me2Si=C(SiMe3)2 to Ph2Si=C(SiMe3)2 there is only a gradual but not principal change of silaethene reactivity.This change is due to increasing polarity and overcrowding of the double bond, that is increasing Lewis acidity and steric hindrance of the unsaturated silicon atom.Certainly, the former silaethene stabilizes thermally by dimerization, the latter by isomerization. - Keywords: Adduct formations, insertions, ene reactions, -, -, -cycloadditions of Ph2Si=C(SiMe3)2 ; Reactivity order of traps ; Reactivity of Me2Si=C(SiMe3)2 and Ph2Si=C(SiMe3)2

On the Problem of the Intermediate Formation of Silanone R2Si=O by Reactions of Silenes with Dinitrogen Oxide

The silaethene Me2Si=C(SiMe3)2 (1a; unstable; from 1a * Ph2C=MSiMe3 = 4) forms with N2O an unstable cycloadduct, which decomposes under isomerization or cleavage.It was not possible to decide clearly, whether the last reaction, which leads to (Me3Si)2CN2 and polymers with (Me2SiO)n groups, proceeds with intermediate formation of silanone Me2Si=O or not (no trapping product with Et3SiH, but with Me3SiCl).The silanimines Me2Si=NSitBu3 (2a; unstable; from 2a * tBu3SiN3 = 7) and tBu2Si=NSitBu3 (2b; metastable) form with N2O unstable cycloadducts, which, under participation of the silanimines, react into products (10) being composed of a molecular silanone and a molecule silanimine.As has been shown by trapping experiments with Et3SiH, Me3SiCl, or Me3SiOMe, latter reaction involves unstable free silanones Me2Si=O (3a) or tBuSi=O (3b) as intermediates. 3b, generated in benzene from 2b/NO2 in the presence of equimolar amounts of tetrahydrofuran (THF), obviously forms an adduct 3b*THF, which is trapped by excess 2b.When 3b is produced in THF as solvent, the silanone starts THF polymerization, indicating a high Lewis acidity of silanones.

Storing of the Labile Silaethene Me2Si=C(SiMe3)2 with Benzophenone

Benzophenone Ph2C=O is able to "store" the silaethene Me2Si=C(SiMe3)2 (1), produced from Me2SiX-CLi(SiMe3)2 (X = F, Br, Ph2PO4), under formation of a cycloadduct (2b).At about 100 deg C, 2b by way of 1 transfers into the cycloadduct of 1 and Ph2C=O (3b), which in the course of transformation decomposes visibly (in the absence of Me3SiCl) or only by traces (in the presence of Me3SiCl) to secondary products.In the presence of ROH (R = H, Me, tBu, MeCO) or PhN=NSiMe3 or RN3 (R = tBu, Me3Si) or 2,3-dimethylbutadiene (dmb) about 100 deg C 2b and 3b form by way of 1 insertion products of 1 into the OH bond of ROH or a cycloadduct of 1 and PhN=NSiMe3 or cycloadducts of 1 and RN3 or cycloadduct and an ene reaction product of 1 and dmb.The rate constants/half lives of the first order transformation of 2b into 3b or of the first order decomposition of 2b or of 3b in the presence of reactive traps for 1 (ROH, Me3SiN3; benzene as solvent) are in the order of 0.3E-4 s-1/τ1/2 = 7 h (2b --> 3b; 90 deg C) 3E-4 s-1/τ1/2 = 3/4 h (2b + traps; 90 deg C), 0.4E-4 s-1/τ1/2 = 5 h (3b + traps, 110 deg C). - Keywords: Silaethene Me2Si=C(SiMe3)2, Insertions, Cycloadditions, Kinetic Studies

Preparation of Silan- and Germanimines Me2E=NR (E = Si, Ge) from Sila- and Germadihydrotriazoles

Sila- or germaethene Me2E=C(SiMe3)2 quantitatively react with azidoalkanes or -silanes RN3 nMe3-nSi, Ph3Si, (Me3Si)2NMe2E, Me2SiN3> at -78 deg C by cycloaddition to form sila- or germadihydrotriazoles 3 and 4, respectively.The latter decompose partly below (E = Si, R = silyl), partly at or above room temperature (E = Si, R = alkyl; E = Ge) in a first-order reaction by isomerization into diazomethane derivatives as well as by cycloreversion into (Me3Si)2C=N=N and silan- or germanimines Me2E=NR (rate constants: Table 1).The saturated compounds Me2E= NR are formed as short-lived intermediates.Their stabilization, as a rule, takes place by dimerization and, in exceptional cases, by reaction with the silan- or germanimine sources (R = SiMe3) or by intramolecular migration processes .

Adduct Formation and Reactivity of Silane- and Germaneimines Me2E=NR (E = Si, Ge)

Silane- and Germaneimines Me2E=NR (E = Si, Ge; R = silyl), generated as reactive intermediates by thermal cycloreversion from cycloadducts of Me2E=C(SiMe3)2 or Me2E=NR with silyl azides RN3, combine with reactants a (e.g.NEtMe2) under addition (formation of adducts 7), with a-b under insertion into the a-b bond (formation 13-16), with a=b (e.g.RN=EMe2, O=CPh2) under cycloaddition (e.g. formation of 17, 18), with a=b=c (e.g.R'N=N=N) under cycloaddition (e.g. formation of 19, 20), and with a=b-c-H (e.g.CH2=CR-CH2-H, O=CMe-CH2-H) under ene reaction (formation of 21-24). cycloaddition of Me2Si=NR with organic 1,3-dienes (e.g.CH2=CR-CR=CH2, cyclopentadiene) is not observed.By comparison with ethenes Me2E=C(SiMe3)2, imines Me2E=NR have greater tendency for insertion and lesser tendency for cycloaddition; by comparison with silaneimines Me2Si=NR, germaneimines Me2Ge=NR are possibly less Lewis acidic.

Storage of Silan- and Germanimines Me2E=NR (E = Si, Ge) by Way of Sila- or Germadihydrotetrazoles

Silan- and germanimines Me2E=NR (1, 2) ntBu3-n, SiPh3, EMe2N(SiMe3)2> react with azidoalkanes or -silanes R'N3 ntBu3-n, SiPh3, SiMe2N(SiMe3)2> by cycloaddition to form sila- or germatetrazoles 5, 6 (in addition, insertion products of Me2E=NR in the R'N bond of the azides and others are formed in some cases).The sila- or germadihydrotetrazoles decompose at raised temperatures in a first-order reaction, reversing their formation by cycloreversion into azides R'N3 or RN3 and imines Me2E=NR or Me2E=NR' (rate constants: Table 1).Consequently, azides operate as stores for silan- and germanimines.The unsaturated systems are formed only as short-lived intermediates.Their stabilization, as a rule, takes place by dimerization and/or insertion of the imines into the RN or R'N bond of the azides, formed as well by thermolysis of dihydrotetrazoles.

Reactivity of the Labile Silaethene Me2Si=C(SiMe3)2, Stored as Ph2C=NSiMe3 Adducts

Silaethene Me2Si=C(SiMe3)2 (1), stored as Ph2C=NSiMe3 adducts and regenerated from the adducts at about 100 deg C as a reaction intermediate, combines with reactants a-b (e.g.HO-H, RO-H, RCOO-H, RS-H, RHN-H, Ph2CN-H, RO-SiR3, R2N-SiR3, Ph2CN-SiR3, Cl-GeR3, Cl-SnR3) with insertion into the a-b bond, with a=b (e.g.O=CPh2, Me3SiN=CPh2, CH2=CHOMe, cis-piperylene), a=b=c (e.g.RN=N=N, O=N=N), a=b-c=d (e.g. butadiene, isoprene, trans-piperylene, 2,3-dimethylbutadiene, cyclopentadiene, anthracene, benzophenone, N-trimethylsilylbenzophenoneimine) under -, - as well as -c ycloaddition and with a=b-c-H (e.g. propene, butenes, isoprene, 2,3-dimethylbutadiene, acetone) under ene reaction.According to relative reaction rates, insertion and -cycloadditions seem to proceed in two reaction steps, whereas -cycloadditions and ene reactions with organic dienes and enes obviously are one step reactions.For reactivities cf.Table I. - Key words: Silaethene Me2Si=C(SiMe3)2, Insertions, Cycloadditions, Relative Reactivities

Reaktivitaet des Silaethens Me2Si=C(SiMe3)2: Thermolyse von (Me3Si)2(Me2XSi)CLi (X z. B. (PhO)2PO2) in Anwesenheit von Silaethen-Faengern

Silaethene Me2Si=C(SiMe3)2 (1), generated as a reaction intermediate by the thermal elimination of LiX from Me2XSi-CLi(SiMe3)2, combines with the reactants a - b (e. g.Me3Si-Cl, Me3Si-OMe) with insertion in the a - b bond, with a = b - c - H (e. g.CH2=CMe