17599-59-6Relevant academic research and scientific papers
Synthesis, Characterization, and Reactivity Studies of Subphthalocyanine Boron Triflate
Wang, Zikuan,Fu, Xuefeng
supporting information, p. 285 - 290 (2017/04/26)
The highly reactive subphthalocyanine boron triflate complex ((subPc)BOTf) was isolated and characterized by X-ray diffraction and spectroscopic methods. The combination of (subPc)BOTf and bis(trimethylsilyl)amide (LiHMDS) yielded a kinetically induced frustrated Lewis pair system capable of activating a variety of substrates such as ethers, amides, and ketones. These reactions demonstrate the high reactivity of (subPc)BOTf toward organic molecules.
The chemical behavior of the silaoxine C22H34OSi3 and silaazetidine C25H43NSi4 towards CO2
S?nger, Inge,Bolte, Michael,Lerner, Hans-Wolfram
, p. 1219 - 1224 (2016/12/09)
When 4,4a-dihydro-3,3-dimethyl-1-phenyl-4,4-bis(trimethylsilyl)-3H-2-oxa-3-sila-naphthaline (silaoxine C22H34OSi3 (3); orthorhombic, space group Pna21, Z=4) was thermolized in a CO2 atmosphere, the co
Indole synthesis: palladium-catalyzed C-H bond amination via reduction of nitroalkenes with carbon monoxide
Hsieh, Tom H.H.,Dong, Vy M.
experimental part, p. 3062 - 3068 (2009/09/05)
Nitroalkenes have been called 'chemical chameleons' due to their versatility in numerous synthetic transformations. Herein, we describe the first transition metal-catalyzed transformation of conjugated nitroalkenes into indoles. Under mild reaction condit
Reactions of lithium hydridosilylamides with carbonyl compounds and mixtures of carbonyl compounds and chlorotrimethylsilane
Schneider, Jan,Popowski, Eckhard,Fuhrmann, Hans
, p. 663 - 672 (2007/10/03)
The lithium hydridosilylamides Me2(H)SiN(Li)R (1: R = CMe3, 2: R = SiMe3) were allowed to react either with the non-enolizable carbonyl compounds CH2=C(Me)CHO, PhCHO and Ph2CO followed by trapping with chlorotrimethylsilane (A), or with mixtures of these carbonyl compounds and chlorotrimethylsilane (B). In the second case the course of the reactions is determined by the carbonyl compound. The composition of the reaction mixtures is nearly the same according to A and B. Main products in the reactions with the aldehydes are the corresponding imines R1CH=NR R1 = CH2=C(Me), Ph) 3, 4, 8, 9 formed by addition of the hydridosilylamides to the C=O group of the aldehydes and subsequent LiOSiMe2H elimination. Partial hydrosilylation of the aldehydes by the hydridosilanolate followed by the trimethylsilylation yields the alkoxydisiloxanes R1CH2OSiMe2OSiMe3 6, 11. In some cases 2 partially reacts under hydrosilylation to give the alkoxydisilazanes R1CH2OSiMe2NHSiMe3 7, 12. The hydrosilylation is the preferred reaction of 1 and 2 with benzophenone. The compounds Ph2CHOSiMe2NHR 13, 14 are obtained. This difference in the reaction behaviour of 1 and 2 towards the aldehydes and benzophenone is mainly due to steric reasons. Depending on the conditions the imines Ph2C=NR 20, 21 may be formed. Ph2CHOSiMe2OSiMe3 (22) is a secondary product of imine formation. In all reactions of 1 and 2 with the carbonyl compounds the corresponding alkoxysilanes R1CH2OSiMe3 (5: R1 = CH2=C(Me), 6: R1 = Ph) and Ph2CHOSiMe3 (15) are generated. Compounds resulting from a reaction of 1 and 2 with chlorotrimethylsilane are produced to minor extent, but only if the molar ratio of amide to carbonyl compounds is not greater than one. The formation of a silanimine intermediate in reaction according to B is not observed.
On the Problem of the Intermediate Formation of Silanone R2Si=O by Reactions of Silenes with Dinitrogen Oxide
Wiberg, Nils,Preiner, Gerhard,Schurz, Klaus
, p. 1407 - 1412 (2007/10/02)
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 N-Trimethylsilyl-benzophenoneimine Ph2C=NSiMe3
Wiberg, Nils,Preiner, G.,Wagner, G.,Koepf, H.,Fischer, G.
, p. 1055 - 1061 (2007/10/02)
N-Trimethylsilyl-benzophenoneimine Ph2C=NSiMe3 is able to "store" the silaethene Me2Si=C(SiMe3)2 (1), produced from Me2SiF-CLi(SiMe3)2, under formation of a - and -cycloadduct (2, 3), respectively.Above 60 deg C (above 120 deg C) 2 or 3 by the way of 1 transform into 1:5 mixture of 2 and 3 (into a 1:1 mixture of the dimer of 1 and the insertion product of 1 into the SiN-bond of Ph2C=NSiMe3).In the presence of 2,3-dimethyl-1,3-butadiene (dmb), 2 or 3 form by way of the reaction of the intermediate 1 with dmb a -cycloadduct (75percent) and an ene reaction product (25percent).The rate constants of the first order decomposition of 2 or 3 in the presence of dmb (80 deg C, solvents like Et2O, C6H6) are in the order of 2 E-4 s-1 (τ1/2 ca. 1 h) and 3 E-5 s-1 (τ1/2 ca. 6 h), respectively. - Key words: Silaethene Me2Si=C(SiMe3)2, Ph2C=NSiMe3-adduct, Kinetic Studies
Reactivity of the Labile Silaethene Me2Si=C(SiMe3)2, Stored as Ph2C=NSiMe3 Adducts
Wiberg, N.,Preiner, G.,Wagner, G.,Koepf, H.
, p. 1062 - 1074 (2007/10/02)
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
Storage of Silan- and Germanimines Me2E=NR (E = Si, Ge) by Way of Sila- or Germadihydrotetrazoles
Wiberg, Nils,Karampatses, Petros,Kim, Chung-Kyun
, p. 1213 - 1222 (2007/10/02)
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.
