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1.
α-Functionalized 2-Methylphenyl Phosphines, 2-(HE? CH2)? C6H4? PH2 (E: O, NR, PH) I. Preparation, Deprotonation and Silylation Behaviour By reaction of different ortho-substituted phenyl phosphonates 2-X? C6H4? PO3R2 (X = COOR, CONHR, PO3R2) with LiAlH4 α-functionalized 2-methylphenyl phosphines 2-(HE? CH2)? C6H4? PH2 (E: O, NPh, PH) are accessible. The title compounds are characterized by deprotonation and silylation experiments.  相似文献   

2.
The stabilization of the labile, zwitterionic “half‐parent” phosphasilene 4 L′Si?PH (L′=CH[(C?CH2)CMe(NAr)2]; Ar=2,6‐iPr2C6H3) could now be accomplished by coordination with two different donor ligands (4‐dimethylaminopyridine (DMAP) and 1,3,4,5‐tetramethylimidazol‐2‐ylidene), affording the adducts 8 and 9 , respectively. The DMAP‐stabilized zwitterionic “half‐parent” phosphasilene 8 is capable of transferring the elusive parent phosphinidene moiety (:PH) to an unsaturated organic substrate, in analogy to the “free” phosphasilene 4 . Furthermore, compounds 4 and 8 show an unusual reactivity of the Si?P moiety towards small molecules. They are capable of adding dimethylzinc and of activating the S?H bonds in H2S and the N?H bonds in ammonia and several organoamines. Interestingly, the DMAP donor ligand of 8 has the propensity to act as a leaving group at the phosphasilene during the reaction. Accordingly, treatment of 8 with H2S affords, under liberation of DMAP, the unprecedented thiosilanoic phosphane LSi?S(PH2) 16 (L=HC(CMe[2,6‐iPr2C6H3N])2). Compounds 4 and 8 react with ammonia both affording L′Si(NH2)PH2 17 , respectively. In addition, the reaction of 8 with isoproylamine, p‐toluidine, and pentafluorophenylhydrazine lead to the corresponding phosphanylsilanes L′Si(PH2)NHR (R=iPr 18 a ; R=C6H5?CH3 18 b , R=NH(C6F5) 18 c ), respectively.  相似文献   

3.
α-Functionalized 2-Methyl Phenylphosphines, 2-(HE? CH2)? C6H4? PH2 (E = O, NR, PH) II. Coordination Behaviour with Metal Carbonyles of Cr, Mo, W The preparation of different carbonyl substituted coordination compounds (M: Cr, Mo, W) of the phosphines 2-(HE? CH2)C6H4? PH2 (E = O, NPh, PH) is described. In one case, after deprotonation of a PH2 group a phosphine/phosphide migration of a W(CO)5 fragment is detected.  相似文献   

4.
5β-androstan-3-ones carrying a 6α-OH group show in their mass spectra a key-ion indicating the loss of water and C-1 to C-4 as C4H5O? particle. 6β-OH isomers lose instead C-1 to C-4 in form of C4H7O?.In 6α-hydroxy-androstan-3-ones differentiation between the connection of the A/B-ring system is possible, because in 5α-isomers the loss of C-3 to C-7 occurs as a C5H6O2 particle, while the 5β-isomers lose the same C atoms as a C5H7O? unit.Compounds with a 6β-OH group in an A/B trans connected ring system show a tendency for thermal water elimination. After rearrangement of the double bond in 4,5 position the typical fragments for 3-keto-Δ4-steroids are obtained.Occasionally a strong influence of a 6-OH group on fragmentation reactions in the D-ring system is observed: The presence of a 6α-OH group in an androstan-3,17-dione enhances the loss of C-16 and C-17 in the form of acetaldehydenol. Also the connection of the A/B-ring system may have a considerable influence on this type of reaction: In 6,17β-dihydroxy-androstan-3-ones only by trans connection of the A/B-ring system, C-16 and C-17 are lost with high probability after water elimination.  相似文献   

5.
Unexpected Reduction of [Cp*TaCl4(PH2R)] (R = But, Cy, Ad, Ph, 2,4,6‐Me3C6H2; Cp* = C5Me5) by Reaction with DBU – Molecular Structure of [(DBU)H][Cp*TaCl4] (DBU = 1,8‐diazabicyclo[5.4.0]undec‐7‐ene) [Cp*TaCl4(PH2R)] (R = But, Cy, Ad, Ph, 2,4,6‐Me3C6H2 (Mes); Cp* = C5Me5) react with DBU in an internal redox reaction with formation of [(DBU)H][Cp*TaCl4] ( 1 ) (DBU = 1,8‐diazabicyclo[5.4.0]undec‐7‐ene) and the corresponding diphosphane (P2H2R2) or decomposition products thereof. 1 was characterised spectroscopically and by crystal structure determination. In the solid state, hydrogen bonding between the (DBU)H cation and one chloro ligand of the anion is observed.  相似文献   

6.
Diorganyltellurium Bis-(dialkylcarbamates) and -(dithiocarbamates) Compounds of the type R2Te(X2CNR′2)2, with R ? C6H5, CH3; R′ ? CH3, C2H5, i-C3H7, c-C6H11, C6H5, and X ? S, are obtained by reaction of dimethyltellurium with tetraorganyl-thiuram-disulfides. Dimethyltellurium diiodide or diphenyltellurium dichloride react with sodium dithiocarbamates or with in situ prepared ammonium dithiocarbamates. Some compounds can be synthesized by reaction of diphenyltellurium oxide with amine in solutions of carbon disulfide. The synthesis of diphenyltellurium- and dimethyltellurium bis-(dimethylcarbamates) results from the interaction of diorganyltellurium diethanolate with dimethylammonium dimethylcarbamate. Decomposition reactions of the compounds in solid and solution are studied 1H-NMR, 13C-NMR, and mass spectroscopically. Diorganyltellurium diethylen-bis-(N,N′-dimethyldithiocarbamates) are obtained by reaction of dimethyltellurium diiodide or diphenyltellurium dichloride and sodium ethylen-bis-(N,N′-dimethyldithiocarbamate) as polymeric products.  相似文献   

7.
4-Amino-1,5-dihydro-2H-pyrrol-2-ones from Boron Trifluoride Catalyzed Reactions of 3-Amino-2H-azirines with Carboxylic Acid Derivatives Reaction of 3-amino-2H-azirines 1 with ethyl 2-nitroacetate ( 6a ) in refluxing MeCN affords 4-amino-1,5-dihydro-2H-pyrrol-2-ones 7 and 3,6-diamino-2,5-dihydropyrazines 8 , the dimerization product of 1 (Scheme 2). Thus, 6a reacts with 1 as a CH-acidic compound by C? C bond formation via C-nucleophilic attack of deprotonated 6a onto the amidinium-C-atom of protonated 1 (Scheme 5). The scope of this reaction seems to be rather limited as 1 and 2-substituted 2-nitroacetates do not give any products besides the azirine dimer 8 (see Table 1). Sodium enolates of carboxylic esters and carboxamides 11 react with 1 under BF3 catalysis to give 4-amino-1,5-dihydro-2H-pyrrol-2-ones 12 in 50–80% yield (Scheme 3, Table 2). In an analogous reaction, 3-amino-2H-pyrrole 13 is formed from 1c and the Li-enolate of acetophenone (Scheme 4). A reaction mechanism for the ring enlargement of 1 involving BF3 catalysis is proposed in Scheme 6.  相似文献   

8.
The first synthesis of a series of 2-aryl(heteroaryl)-4-trifluoromethyl-4,5-dihydro-3H-pyrido[2,3-b][1,4]diazepin-4-ols, where aryl = C6H5, 4-FC6H4, 4-ClC6H4, 4-BrC6H4, 4-CH3C6H4, 4-OCH3C6H4, 4,4′-biphenyl, 1-naphthyl and heteroaryl = 2-thienyl, 2-furyl obtained from the direct cyclocondensation reaction of 4-methoxy-1,1,1-trifluoroalk-3-en-2-ones with 2,3-diaminopyridine in 54-71% yield, is reported. Another alternative and efficient route for the synthesis of a series of 2-aryl(heteroaryl)-3H-pyrido[2,3-b][1,4]diazepin-4(5H)-ones from the reaction 4-methoxy-1,1,1-trichloroalk-3-en-2-ones with 2,3-diaminopyridine, in 54-70% yield, is also reported.  相似文献   

9.
The geometric factors unique to βCH bond addition are discussed. Extended Hückel Molecular Orbital calculatins of the reaction profile for the conversion of [η5-C5H5Co(PH3)C2H5]+ into [η5-C5H5Co(PH3)(C2H4)(C2H4)H]+ shows that an intermediate structure with an agostic interaction is more stable than the octahedral ethylene-hydride complex. The tranformation from the agostic structure to the pentacoordinate species involves a barrier.  相似文献   

10.
The synthesis and characterization of the first parent phosphanylalane and phosphanylgallane stabilized only by a Lewis base (LB) are reported. The corresponding substituted compounds, such as IDipp?GaH2PCy2 ( 1 ) (IDipp=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolin‐2‐ylidene) were obtained by the reaction of LiPCy2 with IDipp?GaH2Cl. However, the LB‐stabilized parent compounds IDipp?GaH2PH2 ( 3 ) and IDipp?AlH2PH2 ( 4 ) were prepared via a salt metathesis of LiPH2?DME with IDipp?E′H2Cl (E′=Ga, Al) or by H2‐elimination reactions of IDipp?E′H3 (E′=Ga, Al) and PH3, respectively. The compounds could be isolated as crystalline solids and completely characterized. Supporting DFT computations gave insight into the reaction pathways as well as into the stability of these compounds with respect to their decomposition behavior.  相似文献   

11.
The iodophosphines PH2J and PHJ2 are formed by the reaction of PH3 with PJ3, P2J4 or J2 respectively. They are stable only in equilibria mixtures together with PH3, PJ3 and P2J4 in the presence of HJ. H-NMR-spectra: PHJ2 doublett ?5,03 ppm, JP? H = 145 Hz, PH2J doublett ?2,95 ppm, JP? H = 168 Hz. P-NMR spectra: PHJ2 doublett +9 ppm, JP? H = 145 Hz, PH2J triplett +156 ppm, JP? H = 168 Hz. The IR-spectra of PH2J and PHJ2 are reported.  相似文献   

12.
Nine novel sulfate-type hybrid surfactants, CmF2m+1C6H4CH(OSO3Na)CnH2n+1 (FmPHnOS: m=4, 6, 8; n=3, 5, 7; C6H4: p-phenylene), with a benzene ring in their molecules were synthesized. Alkanoyl chlorides were allowed to react with iodobenzene in the presence of aluminum chloride to give the corresponding aromatic ketones. The reaction of the ketones with perfluoroalkyl iodides yielded 1-[4-(perfluoroalkyl)phenyl]-1-alkanones as intermediates. The intermediates were allowed to react with methanol in tetrahydrofuran in the presence of sodium borohydride to yield 1-[4-(perfluoroalkyl)phenyl]-1-alkanols. The desired hybrid surfactants were obtained by the reaction of 1-[4-(perfluoroalkyl)phenyl-1-alkanols with sulfur trioxide/pyridine complex in pyridine and by the subsequent neutralization of the products with sodium hydroxide solution. When compared with the conventional hybrid surfactants, CmF2m+1C6H4COCH(SO3Na)CnH2n+1 (FmHnS: m=4, 6; n=2, 4, 6; C6H4: p-phenylene), the new hybrid surfactants thus synthesized were found to have a comparable ability to lower the surface tension of water and a high hydrophilicity. The cmc of FmPHnOS obeyed Kleven’s rule and their occupied areas per molecule increased with increasing m and n with the values between 0.66 and 1.05 nm2. The aggregation number for FmPHnOS micelles ranged from 6 to 45 and the hydrodynamic radius of the micelles was in the range of 1.4-3.1 nm.  相似文献   

13.
A Friedel–Crafts reaction of indolizines with 2-aryl-3H-indol-3-ones catalyzed by B(C6F5)3 is described. This protocol gives access to indolizine derivatives that are valuable building blocks in synthetic and pharmaceutical chemistry. The reaction proceeds under mild conditions, affording various C2-quaternary indolin-3-ones based on indolizine with high yields and regioselectivities. Moreover, the synthetic transformations of the target products were realized by N-methylation and trifluoromethane sulfonation.  相似文献   

14.
Tetraethylphosphonium azide, [P(C2H5)4 ]+[N3 ], was prepared from tetraethyl phosphonium bromide and silver azide. Single crystals of [P(C2H5)4 ]+[N3 ] were grown from dichloromethane/THF (10:1) solution. The structure was determined by single-crystal X-ray diffraction analysis. [P(C2H5)4 ]+[N3 ] crystallizes in the monoclinic space group C 2/c with Z = 4 and unit cell dimensions a = 12.961(6), b = 6.835(3), c = 12.378(6) Å, and β = 100.57(4)°. The attempted preparation of phosphonium azide [PH4]+[N3] from phosphonium iodide and silver azide lead instead to the formation of PH3 and HN3. The instability of [PH4]+[N3] with respect to PH3 and HN3 is in accord with thermodynamic considerations according to which the reaction PH3(g) and HN3(g) to yield [PH4 ]+[N3 ] is thermodynamically unfavorable. (Non SI units employed: kcal ≈ 4.184 J, Å = 10−10 m.) © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:129–132, 1998  相似文献   

15.
The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R3SnCH2P(O)(OR′)R′′ (R′′  OR′, C6H5) via an Arbuzov reaction of R3SnCH2I with P(OR′)3 or C6H5P(OR′)2 (R′′  CH3, C2H5) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br2, HCl, HgBr2) and nucleophilic (NaOH, LiAlH4, LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH4 yields the unsymmetrical methylenebis(phosphines) C6H5P(R)CH2PH2 (R  H, C6H5). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.  相似文献   

16.
Thermal 1,5-sigmatropic rearrangements of one of the methyl group attached at position 3 of 3,3-dimethyl-3H-pyrazolo[3,4-d]pyridazin-4(5H)-ones 1–3 taking place either in a clock-wise or anti-clockwise direction gave N2-methylated products 4–6 and C3a-methylated products 7– 9 . The -7(6)-one derivative 10 and -4,7(5H,6H)-dione derivative 12 gave only N2-methylated products 11 and 13 respectively, and 1,2-dihydro derivative 14 produced after elimination of methane, 15 .  相似文献   

17.
Organoantimony Compounds. VI. Crystalline Phenyl Antimony. Formation and Cleavage with Sodium and Lithium Butyl, respectively Reactions of C6H5SbH2 with C6H5CH ? CH2, C6H5C ? CH and other unsaturated compounds give the corresponding hydrogenated system and phenyl antimony as orange-red crystals and the formula (C6H5Sb)6 · 1 C6H6 1.1 reacts with sodium by cleavage of Sb–Sb bonds forming C6H5SbNa2 and C6H5(Na)Sb–Sb(Na)C6H5. These stibides are suitable materials to prepare tert. stibines, distibines and cyclic stibines. The cleavage of 1 with butyllithium is a complicated reaction and gives beside other stibides also C6H5(C4H9)SbLi which can be characterized as (CH3)3Si–Sb(C4H9)C6H5. The 1H-nmr data of the prepared stibines are discussed.  相似文献   

18.
Preparation of C6H5M(CO5 (M = Mn, Re) and Ortho-Metallated Ketones with a Manganese or Rhenium Ring Member C6H5Mn(CO)5 and C6H5Re(CO)5 were obtained by a new preparation method by a photochemical reaction between M2(CO)10 (M = Mn, Re) and (C6H5)2Hg. The reaction of C6H5Mn(CO)5 with (CH3)2Hg at different reaction conditions yielded the o-metallated benzophenone or the acetophenone; such known o-metallated derivates were prepared as yet by a reaction between the ketones and CH3Mn(CO)5. The ortho-metallated ketones and or were reaction products between Mn2(CO)10 and R2Hg (R?C6H5 or p-(CH3)2NC6H4). On the contrary Re2(CO)10 and (C6H5)2Hg were capable to form the analogous ortho-metallated benzophenone derivatives only by an addition of benzophenone. A substitution reaction of a CO ligand by P(C6H5)3, a fission of the five-membered heterocyclic ring and a phenylation was carried out for some of such o-metallated ketones. The products were characterized by infrared spectroscopic measurements.  相似文献   

19.
Organoantimony Compounds. V. The Reactivity of Phenyl Stibine C6H5SbH2, synthesized by the reduction of C6H5SbCl2 with LiBH4, reacts with LiR under certain conditions forming (C6H5Sb)n and H2 or give by a partially elimination of H2 stibides with a different structure. The latter react with alkyl and aryl halides forming tert. stibines which may be characterized as the corresponding dibromides. The preparation of C6H5SbNa2 and its reaction with C2H5Br, Cl(CH2)4Cl and C6H5(Cl)C?N? N?C(Cl)C6H5 are described.  相似文献   

20.
A variety of arylethynylsilanes (Ar‐C?C? C6H4? C?C)nSiMe4?n were prepared successfully by reaction of the corresponding chlorosilanes Me4?nSiCln with Ar? C?C? C6H4? C?CM (M=Li, MgBr), which was prepared by treatment of ethynyl(diarylethyne)s Ar? C?C? C6H4? C?CH with BuLi or MeMgBr. The ethynyl(diarylethyne)s were readily prepared in good yields by the double‐elimination method: addition of lithium hexamethyldisilazide to a mixture of ArCH2SO2Ph, TMS? C?C? C6H4? CHO, and ClP(O)(OEt)2, followed by desilylation. In the tetrakis(arylethynyl)silanes (Ar? C?C? C6H4? C?C)4Si thus prepared, through‐space conjugation of four triple bonds on the silicon atom emerges as a result of participation of the silicon orbitals in the acetylenic π orbitals. This participation enhances the emissive quantum yields of arylethynylsilanes with an increase in the number of arylethynyl moieties on silicon: quantum yields of emission (ΦF) of 0.72 for (MeOC6H4? C?C? C6H4? C?C)4Si, 0.53 for (MeOC6H4? C?C? C6H4? C?C)2SiMe2, and 0.47 for MeO‐C6H4? C?C? C6H4? C?CSiMe3 were obtained. Although this enhancement effect was also observed in the phenylethynylarylsilane (MeOC6H4? C?C? C6H4)2SiMe2, the bis(arylethynyl)disilane (MeOC6H4? C?C? C6H4? C?C‐SiMe2)2 exhibited non‐enhanced emission.  相似文献   

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