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1.
Isomerisation of the Cyclotrisilazane System — Lithium Salts and Contraction Products 2,2,4,4,6,6-Hexamethyl- and 2,2,4,4,6,6-hexamethyl-1-trimethylsilyl-cyclotrisilazane ( 1, 2 ) react with n-C4H9Li to give the lithium salts 3 and 4 . At 30°C 4 isomerizes in solution to the cyclodisilazane 5 within 15 h. 4 reacts with Me2SiF2 to the substituted compound 6 , whose Li salt contracts yielding the coupled product 7 . 1,3-Bis(fluorodimethylsilyl)-2,2,4,4,6,6-hexamethylcyclotrisilazane isomerizes to the Li salt of the corresponding cyclodisilazane, which reacts with the half-molar quantity of SiF4 to the Si? N? Si? N? Si bridged cyclodisilazane dimer 8 . The tendency of contraction of 4 is discussed on the basis of its crystal structure.  相似文献   

2.
Synthesis, NMR Spectroscopic Characterization and Structure of Bis(1,2-dimethoxyethane-O,O′)barium Bis[1,3-bis(trimethylsilyl)-2-phenyl-1-aza-3-phosphapropenide] Barium-bis[bis(trimethylsilyl)phosphanide] 1 reacts with two equivalents of benzonitrile to give barium bis[1,3-bis(trimethylsilyl)-2-phenyl-1-aza-3-phosphapropenide]; the choice of the solvent determines whether a tris-(tetrahydrofuran)- or a bis(1,2-dimethoxyethane)-complex 2 can be isolated. 2 crystallizes from DME as red cuboids (monoclinic, C2/c, a = 1627.0(3), b = 1836.6(3), c = 1602.5(2) pm; β = 96.071(12)°; V = 4761.7(12); Z = 4; wR2 = 0.0851). The phosphorus atom displays a pyramidal surrounding in contrast to the planar coordination sphere of the nitrogen atom. In addition a twist within the P? C? N skeleton of the heteroallyl anion is observed.  相似文献   

3.
White phosphorus reacts with organic diselenides in a dipolar aprotic solvent in the presence of a base with the formation of tri(alkyl- or aryl-seleno)phosphites in good yield. Tri(methylseleno)phosphitc shows a 31P-chemical shift = ?107 ppni (JP, 77Se = 233 Hz). It is readily oxidizcd in air to the corresponding selenophosphate, (CH3Se)3 P?O, 31P-chemical shift = ?16 ppm. Tri(phenylseleno)phosphite reacts readily with mercury oxide to give the tri(phenylseleno)phosphate, a yellow solid of m.p. 105–110°. It also reacts with sulfur in refluxing benzene solution to give tri(phenylseleno)thiophosphate, also a yellow solid of m.p. 55–58°. However, an attempt to prepare tri(phenylseleno)selenophosphate failed. Under the same conditions as given above, white phosphorus also reacts with di-p-anisyl ditelluride to give tris(p-anisyltelluro)phosphite, shiny, rusty brown crystals which decompose rapidly at room temperature, but are stable for several months when kept in acetonc solution at ?20°.  相似文献   

4.
The CuCl-catalyzed Reaction of Trimethylsilyl(t-butyl)chlorophosphane with Dimethylzirconocene: An Example for Tandem Catalysis t-BuP(SiMe3)Cl was prepared from t-BuP(SiMe3)2 and hexachloroethane and reacted in situ with Cp2ZrMe2 in the presence of catalytic amounts of copper(I) chloride yielding t-Bu(Me)P? P(Cl)t-Bu ( 1 ) (2 : 1 reaction) or t-Bu(Me)P? P · (Me)t-Bu ( 2 ) (1 : 1 reaction) and Cp2ZrCl(Me). To understand the course of reaction, the reaction of dimethylzirconocene with CuCl and the decomposition of t-BuP(SiMe3)Cl in the presence of CuCl and tetrachloroethene were studied. The results suggest that CuCl reacts with t-BuP(SiMe3)Cl in the presence of C2Cl4 to give t-Bu(Cl)P? P(Cl)t-Bu ( 3 ); simultaneously, CuCl reacts with Cp2ZrMe2 with formation of methylcopper, which reacts with 3 to give 1 or 2 , respectively.  相似文献   

5.
Stabilization of ? P?C〈 Bonds by Cyclic Silylhydrazones 1,2-Diaza-3-sila-5-cyclopentenes unsubstituted at the 4-position react after lithiation with halophosphanes and -arsanes to give 1 – 4 . The 4-methylated ring 5 reacts analogously with F2P? N(SiMe3)2 to give 6 , but exchanges the dimethylsilyl group of the ring in reaction with PCl3, to give 1,2-diaza-3-phospha-3,5-cyclopentadien 7 . The phosphaethenes 8 and 9 are formed from 4-trimethylsilylsubstituted lithiated rings by reaction with difluorophosphanes, F2PR (R = N(SiMe3) CMe3, N(SiMe3)2) and elimination of LiF and chlorosilane.  相似文献   

6.
3-Hydroxythietane is readily oxidized by hydrogen peroxide in acetone or acetic acid solution at 0°C to give 3-hydroxythietane-1-oxide. 3-Thietyl acetate is oxidized similarly. 3-Hydroxythietane-1-oxide reacts vigorously with SOCl2 in benzene, with the formation of bis-2, 3-dichloropropyl disulfide. 3-Hydroxythietane-1,1-dioxide reacts with phosgene to give 3-thietyl-1, 1-dioxide chloroformate, which gives with diethylamine 3-thietyl-1, 1-dioxide N, N-dimethylcarbamate. Sodium peroxide and barium perbenzoate with the chloroformate give the corresponding di-(3-thietyl-1, 1-dioxide) peroxydicarbonate and 3-thietyl-1, 1-dioxide perbenzoate.  相似文献   

7.
Transmetallation of Tin(II) in [Sn(μ3‐PSitBu3)]4 by Barium – from Sn4P4 Heterocubane Structures to Heterobinuclear Cage Compounds with a Central BanSn4?nP4 Heterocubane Polyhedron (n = 1, 2 and 3) For the preparation of compounds of the type [BanSn4?n(PSitBu3)4] (n = 1 ( 2 ), 2 ( 3 ) and 3 ( 4 )) two synthetic routes are applicable: in the transmetallation reaction homometallic [Sn4(PSitBu3)4] ( 1 ) reacts with barium metal and in a deprotonation reaction (metallation) tri(tert‐butyl)silylphosphane reacts simultaneously with (thf)2Ba[N(SiMe3)2]2 and Sn[N(SiMe3)2]2. During the transmetallation reaction mixtures of the heterobimetallic cage compounds 2 to 4 are obtained, however, analytically pure compounds 2 and 3 are accessible by the metallation reaction. Compound 4 is formed as a minor product together with 3 . Due to the larger Ba‐P bond lengths compared to the Sn‐P values the substitution of tin by barium leads to strong distortions of the heterocubane moiety. With NMR‐spectroscopic experiments one could show that all the above mentioned compounds form BanSn4?nP4 heterocubane cage structures.  相似文献   

8.
Vinod Kumar 《合成通讯》2013,43(16):2385-2388
N‐tert‐Butyl‐N‐chlorocyanamide reacts with sulfur mustard instantaneously to give a corresponding nontoxic sulfoxide in quantitative yield. The transformation is selective and takes place in semi‐aqueous medium (CH3CN/H2O, 1∶1), even at subzero temperatures.  相似文献   

9.
Primary diazoketones, R? CO? CHN2, are O-protonated in HF? SbF5? SO2 or FSO3H? SbF5? SO2 at ?60°, as observed by NMR. The OH-proton resonates at 9.3–9.6 δ and is coupled with H? C 1 (J = 1–2.5 Hz). Secondary diazoketones, R? CO? C(N2)? R, when protonated, give an OH-singlet at 8.85 δ. The assignments are corroborated by use of deuterated diazoketones, R? CO? CDN2, or deuterated acid, FSO3D. Primary diazoketones react with FSO3H at ?60° to ?15°, giving products assigned the fluorosulfate structure, R? CO? CH2? OSO2F; they do not exchange H? C 1 with solvent before or during decomposition. Intermediate C-protonated diazonium ions and α-oxo-carbonium ions (vinyl carbonium ions) have not been identified. 3-Diazo-4-methyl-2-pentanone (VIII) reacts with FSO3H at ?15°, eliminating N2 and giving protonated mesityl oxide by a strictly intramolecular hydride shift.  相似文献   

10.
Crystal Structure of Bis[lithium-tris(trimethylsilyl)hydrazide] and Reactions with Fluoroboranes, -silanes, and -phospanes Tris(trimethylsilyl)hydrazine reacts with n-butyllithium in n-hexane to give the lithium-derivative 1 . The reaction of 1 with SiF4, PhSiF3, BF3 · OEt2, F2BN(SiMe3)2 and PF3 leads to the substitution products 2–6 . The 1,2-diaza-3-bora-5-silacyclopentane 7 is formed by heating (Me3Si)2N? N(SiMe3)(BFNSiMe3)2 ( 5 ) at 250°C. In the reaction of (Me3Si)2N? N(SiMe3)PF2 ( 6 ) with lithiated tert.-butyl(trimethylsilyl)amine the hydrazino-iminophosphene (Me3Si)2N? N = P? N(SiMe3)(CMe3) ( 8 ) is obtained. In the molar ratio 2:1 1 reacts with SiF4 and BF3 · OEt2 to give bis[tris(trimethylsilyl)hydrazino]silane 9 and -borane 10 .  相似文献   

11.
S-Transfer Reactions with Bis(imidazolo)sulfane and Silylated Sulfur-Nitrogen Compounds: Synthesis of Functionally Thiosulfurdiimides Sulfinimideamides Rs(NSiMe3)N(SiMe3)2 ( 1 ) (R = t-Bu or Ph) react with bis(imidazolo)sulfane via SIVII-? redox transimination”? yielding thiosulfurdiimides RSN ? S ? NSiMe3 ( 2 ), which reacts with further bis(imidazolo)sulfane to give dithiosulfur-dimides RSN ? NSR ( 3 ). Solvolysis of 2 with MeOH gives the corresponding NH-compounds RSN ? S ? NH ( 4 ).  相似文献   

12.
The thermal behaviour of BaC2O4sd0.5H2O and BaCO3 in carbon dioxide and nitrogen atmospheres is investigated as part of a study about the thermal decomposition of barium trioxalatoaluminate. For this purpose thermogravimetry, differential thermal analysis, differential scanning calorimetry and high temperature X-ray diffraction were used. An infrared absorption spectrum of BaC2O4·0.5H2O was scanned at room temperature.At increasing temperature, in dry nitrogen, the hydrate water of BaC2O4· 0.5H2O is split off, followed by the oxalate decomposition. A part of the evolved carbon monoxide disproportionates, leaving carbon behind. At higher temperatures the latter reacts with barium carbonate, previously formed. Finally the residual solid barium carbonate decomposes into barium oxide and carbon dioxide.In dry carbon dioxide atmosphere an analogous dehydration occurs, followed by oxalate decomposition. Under these conditions the carbon formation is fully suppressed, and as a consequence no secondary reaction occurs. The barium carbonate decomposition is shifted to much higher temperatures, at a low rate in the solid phase, a strongly accelerated one at the onset of melting, and a moderated one when the melt is saturated with barium carbonate. The two phase transitions of BaCO3 are detectable in both atmospheres mentioned.  相似文献   

13.
The frustrated Lewis pair (FLP) Mes2PCH2CH2B(C6F5)2 ( 1 ) reacts with an enolizable conjugated ynone by 1,4‐addition involving enolate tautomerization to give an eight‐membered zwitterionic heterocycle. The conjugated endione PhCO‐CH?CH‐COPh reacts with the intermolecular FLP tBu3P/B(C6F5)3 by a simple 1,4‐addition to an enone subunit. The same substrate undergoes a more complex reaction with the FLP 1 that involves internal acetal formation to give a heterobicyclic zwitterionic product. FLP 1 reacts with dimethyl maleate by selective overall addition to the C?C double bond to give a six‐membered heterocycle. It adds analogously to the triple bond of an acetylenic ester to give a similarly structured six‐membered heterocycle. The intermolecular FLP P(o‐tolyl)3/B(C6F5)3 reacts analogously with acetylenic ester by trans‐addition to the carbon–carbon triple bond. An excess of the intermolecular FLP tBu3P/B(C6F5)3, which contains a more nucleophilic phosphane, reacts differently with acetylenic ester examples, namely by O? C(alkyl) bond cleavage to give the {R‐CO2[B(C6F5)3]2?}[alkyl‐PtBu3+] salts. Simple aryl or alkyl esters react analogously by using the borane‐stabilized carboxylates as good leaving groups. All essential products were characterized by X‐ray diffraction.  相似文献   

14.
Synthesis and Crystal Structure of the Trimeric [(Me3Si)2CH]2Al? CN Tetrakis[bis(trimethylsilyl)methyl]dialane(4) 1 with an Al? Al bond reacts with tert-butyl isocyanide in the molar ratio of 1:2 within three days to give a mixture of several unknown products, from which the title compound 4 is isolated in a 26% yield by recrystallization from n-pentane. 4 is a trimer in the solid state via Al? C?N? Al bridges showing a nine-membered Al3C3N3 heterocycle in a boat conformation. In contrary to the reaction with phenyl isocyanide the expected dark red product of the twofold insertion into the Al? Al bond under formation of a carbon-carbon single bond is detected only spectroscopically as a minor by-product.  相似文献   

15.
Thermolysis of tetrazolopyrazine ( 1 ) in organic solvents gives pyrazinylnitrene ( 2 ) which undergoes ring contraction to 1-cyanoimidazole ( 3 ). 7-Methyl-5-methylthio-tetrazolo[1,5-c]pyrimidine ( 4 ) likewise gives 1-cyano-2-methylthio-4-methyl-imidazole ( 6 ). The two tetrazoles also undergo ring contraction to 1-cyanoimidazoles by gas chromatography, and 1 gives a low yield of 3 by photolysis. Thermolysis of 1 and 4 in cyclohexane gives aminopyrazine ( 7 ) and 6-amino-4-methyl-2-methylthio-pyrimidine ( 8 ), respectively. Tetrazolo[1,5-a]pyrimidines ( 9 ) give only 2-aminopyrimidines ( 10 ). 1-Cyanoimidazole, formed by thermolysis of 1 in acetic acid, reacts further to give 1-acetylimidazole, which with more acetic acid gives imidazole and acetic anhydride. An earlier report [2] of ring expansion of pyrazinylnitrene in acetic acid is discredited. In protic deuteriated solvents (D3O, CH3OD), tetrazolopyrazine reacts as an enamine, specifically exchanging H? C(6) for deuterium.  相似文献   

16.
MMe5(dmpe) (M = Nb or Ta, dmpe = Me2PCH2CH2PMe2) reacts with H2 (500 atm) and dmpe in THF at 60°C to give MH5(dmpe)2? NbH5(dmpe)2 readily reacts with two mol of CO or ethylene (L) to give NbHL2(dmpe)2. The exchange of the hydride ligand with the ethylene protons in NbH(C2H4)2(dmpe)2 is not rapid on the 1H NMR time scale (60 MHz) at 95°C.  相似文献   

17.
Nitric oxide reacts with trimethylaluminium to give complexes Me3AlNO and Me3Al(NO)2 which appear to be derivatives of N-methyl-N-nitrosohydroxylamine.  相似文献   

18.
Cyclocondensations with Primary Sulfinimidamides: Synthesis of Six-membered Rings with λ4-Thiadiazine and λ4-Thiatriazadiphosphorine Constitution 1,1-Dimethyl-ethanesulfinimidamide ( 1 ,) reacts with tetracyanoethylene by elimination of hydrogen cyanide to give the 1,2,6-thiadiazine 2 . In the cyclocondensation reaction of 1 , with tetrachloromethane and phosphines Ph2PR′ (R′ = Ph2PNH or Ph) the 1,2,4,6,3,5-thiatriazaphosphorine 3 a , and the ring-open compound [t-BuS(NH)NHPPh3]Cl ( 4 ,), respectively, are formed by P? N-bond formation. The compounds are characterized by IR, MS and NMR data, and for 3a , further by X-ray structure analysis (space group P1 , Z = 2).  相似文献   

19.
Acyclic and Cyclic Silylhydrazones and Hydrazonylsilanes Dimethylketone-di-tert-butylmethylsilylhydrazone ( 1 ) is obtained in the reaction of the silylhydrazine and dimethylketone by condensation. Di-tert-butyldifluorosilane reacts with lithiated hydrazones to give fluorosilylhydrazones 2–4 , (CMe3)2SiF? NH? N = CRR′, ( 2 : R=Me, R′=CMe3; 3 : R,R′=CHMe2; 4 : R,R′=Ph). The bis(hydrazonyl)silane 5 , (CMe3)2Si(NH? N=CPh2)2, is formed in a molar ratio 1:2. Tris( 6 )- and tetrakis(hydrazonyl)silanes ( 7 ) are obtained from CMe3SiF3 ( 6 ), SiF4 ( 7 ), and lithiated tert-butylmethylketon-hydrazone. The lithium derivatives 8–11 are formed in the reaction of 1–4 with butyllithium. Bis(silyl)hydrazones ( 12–15 ) are the result of the reaction of halogensilanes and the lithium derivatives of 1(8), 2(9) and 3(10); 12 : (CMe3)2SiMe(CMe3SiF2)-N? N=CMe2, 13 : (CMe3)2MeSi(PhSiF2)N? N=CMe2, 14 : (CMe3)2SiF(Me3Si)N? N=C(Me)(CMe3), 15 : (CMe3)2SiF (SiMe3)N? N=C(CHMe2)2. Saltelimination out of 10 und 11 leads to the formation of the first bis(imino)-2,2,4,4-cyclodisilazanes, 16 :[(CMe3)2 SiN? N=C(CHMe2)2]2, 17 : [(CMe3)2SiN? N=CPh2]2. Cyclisation occurs in the reaction of 12 und 14 with tert-butyllithium, 2-silyl-1,2-diaza-3-sila-5-cyclopentenes ( 18 and 19 ) are formed. Dilithiated 1 reacts with SiF4 to give the spirocyclic compound 20 . HF-elimination from 18 and dimerisation of the intermediate diazasilacyclopentadiens lead to the formation of the tricyclus 21 .  相似文献   

20.
Two Ways to Si-functional Cyclosilanes — Crystal Structure of 1,3,6,8,10,12-Hexa-aza-2,4,5,7,9,11-hexasila-dispiro [4.1.4.1]dodecan Aminochlorosilanes [RSiCl2NHCMe3, R ? Cl ( 1 ), H ( 2 )] are obtained in the reaction of the chlorosilanes with LiNHCMe3. HSiCl2N(iso-Bu)SiMe3 ( 3 ) is formed in the reaction of HSiCl3 and LiN(iso-Bu)SiMe3. HSiCl3 reacts with LiN(CMe3)SiMe3 under LiCl and Me3SiCl elimination to give the cyclodisilazane [(HSiCl? NCMe3)2 ( 4 )]. In addition to C6H5SiCl2N(CMe3)SiMe3 ( 5 ), the main product of the reaction of trichloro-phenylsilane with LiN(CMe3)SiMe3 is C6H5SiCl2NHCMe3 ( 6 ). 3 loses Me3SiCl thermally, giving the cyclotrisilazane [(HSiCl? N? iso-Bu)3 ( 7 )]. 5 loses iso-butane thermally with formation of C6H5? SiCl2? NH? SiMe3 ( 8 ). 1 , 2 and 6 react with LiC4H9 under butane and LiCl elimination to give the cyclodisilazes [(RSiCl? NCMe3)2, R ? H ( 4 ), Cl ( 9 ), C6H5 ( 10 )]. 4 is fluorinated to (HSiF? NCMe3)2 ( 11 ) by NaF. The alcoholysis of 4 leads to the formation of [(H(RO)Si? NCMe3)2, R ? Me ( 12 ), C6H5 ( 13 )], the aminolysis to [(H(NR2)Si? NCMe3)2, R ? Me ( 14 ), C2H5 ( 15 )], only one chloro atom of 4 is substituted in the reaction with H2NCMe3 ( 16 ). 4 reacts with lithium to give the 1,3,6,8,10,12-hexa-aza-2,4,5,7,9,11-hexasila-dispiro[4.1.4.1]dodecan ( 17 ), for which the crystal structure is reported.  相似文献   

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