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1.
Abstract

O-Ethyl-N-alkylphosphoro(thioureido)thioates(II) were synthesized by the addition of O-ethyl-N-alkylphosphor-isothiocyanatidothioates(I) with corresponding alkyl or aryl amines, in which R=C1, -C3, R1, R2=H, alkyl or aryl. Their structures were confirmed by IR, 1H NMR, MS and elemental analysis. The results of bioassay showed that they had fairly good fungicidal and herbicidal activities. When II(R1=H,R2=i-Pr,Ph,aryl etc.) reacted with chloroacetyl chloride, the compounds III were given.  相似文献   

2.
An efficient and regioselective procedure for the synthesis of a series of alkyl(aryl/heteroaryl) substituted 3-trifluoromethyl-1H-1-phenylpyrazoles and alkyl 3-carboxylate analogs, from the cyclocondensation reactions of 4-alkoxy-1,1,1-trihaloalk-3-en-2-ones [CX3C(O)CR2=CR1(OMe/OEt), where R1 = H, Me, Ph, 2-Furyl; R2 = H; R1-R2 = -C4H8- and X = F, Cl] and 1-phenylsemicarbazide in an acidified alcoholic medium (R3OH/H2SO4), where R3 = Me, Et, Pri was successfully applied and is described here in detail.  相似文献   

3.
It is demonstrated for the first time that the site-selectivity for the Fe+-mediated C? H bond activation of aldimines R1N?CHR2 (R1, R2 = alkyl) involves the alkyl chain R1 by a factor ≥ 12 in comparison to the alkenyl part R2. This finding explains previous observations that dehydrogenation of intermediates formed by alkene loss from either R1 or R2 of R1N?CHR2/Fe+ preferentially involves the alkyl part.  相似文献   

4.
Abstract

The reactions of a variety of electrophiles with the N-silyl-P-trifluoroethoxyphosphoranimine anion Me3Sin°P(Me)(OCH2CF3)CH? 2 (1a), prepared by the deprotonation of the dimethyl precursor Me3SiN[dbnd]P(OCH2CF3)Me2 (1) with n-BuLi in Et2O at-78°C, were studied. Thus, treatment of 1a with alkyl halides, ethyl chloroformate, or bromine afforded the new N-silylphosphoranimine derivatives Me3SiN[dbnd]P(Me)(OCH2CF3)CH2R [2: R = Me, 3: R = CH2Ph, 4: R = CH[sbnd]CH2, 5: R = C(O)OEt, and 6: R = Br]. In another series, when 1a was allowed to react with various carbonyl compounds, 1,2-addition of the anion to the carbonyl group was observed. Quenching with Me3SiCl gave the O-silylated products Me3SiN[dbnd]P(Me)(OCH2CF3)CH2°C(OSiMe3)R1R2 [7: R 1 = R 2 = Me; 8: R 1 = Me, R 2 = Ph; 9: R1 = Me, R 2 = CH[sbnd]CH2; and 10: R 1 = H, R 2 = Ph]. Compounds 2–10 were obtained as distillable, thermally stable liquids and were characterized by NMR spectroscopy (1H, 13C, and 31P) and elemental analysis.  相似文献   

5.
In the pursuit of biologically active compounds we required as a key intermediate 2,3-dihydro- 1,3-benzoxaz-bones having a halomethylene moiety at C(2), i.e. 3 (R2 = H or alkyl, R3 = CH2X). The standard procedure for the preparation of this class of compounds is the condensation of salicylamide derivatives 1 with the proper aldehyde1-5 and ketone5,6. Usually, hydrochloric acid or sulphuric acid is used as catalyst and the water formed is cocornmittently removed using a dehydrating agent or by azeotropic destillation7. These procedures did not serve our purpose as the required α-substituted aldehyde or ketone as such is unstable under the conditions employed. Here we report that employment of acetals and ketals 2 affords the desired compound 3; yields are appreciable when the proper reaction conditions are used.  相似文献   

6.
Ni‐catalyzed cross‐coupling of unactivated secondary alkyl halides with alkylboranes provides an efficient way to construct alkyl–alkyl bonds. The mechanism of this reaction with the Ni/ L1 ( L1 =transN,N′‐dimethyl‐1,2‐cyclohexanediamine) system was examined for the first time by using theoretical calculations. The feasible mechanism was found to involve a NiI–NiIII catalytic cycle with three main steps: transmetalation of [NiI( L1 )X] (X=Cl, Br) with 9‐borabicyclo[3.3.1]nonane (9‐BBN)R1 to produce [NiI( L1 )(R1)], oxidative addition of R2X with [NiI( L1 )(R1)] to produce [NiIII( L1 )(R1)(R2)X] through a radical pathway, and C? C reductive elimination to generate the product and [NiI( L1 )X]. The transmetalation step is rate‐determining for both primary and secondary alkyl bromides. KOiBu decreases the activation barrier of the transmetalation step by forming a potassium alkyl boronate salt with alkyl borane. Tertiary alkyl halides are not reactive because the activation barrier of reductive elimination is too high (+34.7 kcal mol?1). On the other hand, the cross‐coupling of alkyl chlorides can be catalyzed by Ni/ L2 ( L2 =transN,N′‐dimethyl‐1,2‐diphenylethane‐1,2‐diamine) because the activation barrier of transmetalation with L2 is lower than that with L1 . Importantly, the Ni0–NiII catalytic cycle is not favored in the present systems because reductive elimination from both singlet and triplet [NiII( L1 )(R1)(R2)] is very difficult.  相似文献   

7.
The reaction of thiobenzamide with 3-alkoxy-3-aryl(or alkyl)-2-cyanopropenenitriles 1 and sodium 2-propoxide in 2-propanol afforded after acidic treatment 6-aryl(or alkyl)-5-cyano-2-phenyl-4-thioxo-3,4-dihydropyrimidines 3 through formation of the 3-aryl(or alkyl)-2-cyano-3-thiobenzamidopropenenitrile 2 that has been isolated in one case ( 2a , R1 = Ph).  相似文献   

8.
In order to replace silicones in some of their biomedical applications, e.g. syringe lubrication, implants ets., a series of digermoxanes (R1R2R3Ge)2O (R = n–alkyl, aryl) were synthesized. These compounds are thermally stable oils; their viscosities, depending on the nature of substituents, lie in the range 1–72 cPo (mPa s) at 20°C.  相似文献   

9.
Abstract

A series of derivatives R1R2P(X)R3, where R1=R2=Ph. R3= -CH=CH-Me, X=O(I); R1=Me, R2=Ph, R3= -CH=CH2, X=O(II); R1=R2=Ph, R3= -CH=CH2, X=Se(III) and R1R2P(O)-CH2C(O)OX, where R1=Ph, R2= -CH=CH2, X=Ment?(IV); R1=Ph-2-OMe, R2=Ph, X=Ment?(V); R1=R2=CH2Ph, X=Et(I), were investigated by means of dipole moments method. The problem of conjugation in phosphorylethylenes and conformation behaviour of phosphorylacetates was considered. DM (exp.) of (I-IV), determined in CC14 solution are 4.48(I), 4.27(II), 4.97(III), 4.21(IV), 5.21(V) and 4.02 D (VI). The intramolecular electronic interactions of phosphoryl group with unsaturated fragment did not displays in polarity properties of compounds (I-III). The experimental dipole moments of derivatives (I-III) are equal to the calculated values of DM. DM (IV-VI) is very sensitive to orientation of the P=O and C=O polar bonds. Because DM (exp.) of these compounds very sensitive to its orientation. DM (calc.) for cis- and trans- orientation of P=O and C=O dipoles are really different, that allows to drow the conclution that, in the contrast to the crystal state, the corresponded dipoles prefer an anti array in solution.  相似文献   

10.
Electrochemical reduction of 1-X-1-R1-5-methyl-2-phenyl-7-R2-1,2-dihydro-1,2,4,3-tri-azaphospholo[4,5-a]quinolines1–5 (1: X is the lone electron pair (LEP), R1=Et2N, R2=Me;2: X=LEP, R1=Ph, R2=H;3: X=S, R1=Et2N, R2=H;4: X=LEP, R1=Et2N, R2=H;5: X=LEP, R1=MeO, R2=H) in DMF with 0.1M Bu4NI as supporting electrolyte is reversible and results in metastable radical anions. Radical anions of compounds1–3 efficiently reduce 1,2-dichloro-2-methoxycarbonyl-2-methylcyclopropane both in the presence and in absence of Ni11 ions. Effective reduction rate constants have been evaluated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2088–2091, November, 1999.  相似文献   

11.
Abstract

Element-substituted acylphosphines are stable in form 2 R1P(ERn)COR2 (A), when E=Ge, Sn, Sb, P, T1 and in form R1 P=C(OERn)R2 by NMR data. The reaction  相似文献   

12.
Bis(1-aminoguanidinium) sulfate monohydrate (AG2SO4 … H2O, 1), bis(1,3-diamino-guanidinium sulfate (DAG2SO4, 2), bis(1,3,5-triaminoguanidinium) sulfate dihydrate (TAG2SO4 … 2 H2O, 3) and bis(azidoformamidinium) sulfate (AF2SO4, 5) were synthesized and characterized by multinuclear NMR, IR, and Raman spectroscopy and elemental analysis. In the synthesis of 3, double protonated triaminoguanidinium sulfate (HTAGSO4, 4) was obtained as a byproduct. The molecular structures of 15 in the crystalline state were determined by low-temperature single crystal X-ray diffraction. 1: orthorhombic, Pnma, a = 6.7222 (8) Å, b = 14.153 (2) Å, c = 11.637 (1) Å, V = 1107.1(2) Å3, Z = 4, ρcalc.= 1.586 g cm?3 R1 = 0.0442, wR2 = 0.1007 (all data). 2: hexagonal, P6122, a,b = 6.6907 (1) Å, c = 43.4600 (8) Å, γ= 120°, V = 1684.86 (5) Å3, Z = 6, ρcalc.= 1.634 g cm?3, R1 = 0.0321, wR2 = 0.0714 (all data). 3: monoclinic, C2/c, a = 9.6174 (8) Å, b = 22.858 (1) Å, c = 6.7746 (5) Å, β= 109.49 (1), V = 1404.0 (4) Å3, Z = 4, ρcalc.= 1.620 g cm?3, R1 = 0.0292, wR2 = 0.0781 (all data). 4: monoclini c, P21/c, a = 8.9998 (9), b = 6.3953 (6), c = 13.3148(12) Å, β= 99.679 (8), V = 755.44 (13) Å3, Z = 4, ρcalc.= 1.778 g cm?3, R1 = 0.0305, wR2 = 0.0809 (all data); 5: orthorhombic, Pbca, a = 11.3855 (9), b = 7.1032 (6), c = 12.807 (1) Å, V = 1035.74 (14) Å3, Z = 4, ρcalc.= 1.720 g cm?3, R1 = 0.0389, wR2 = 0.0862 (all data).  相似文献   

13.
Zusammenfassung -Substituierte -Acylvinylphosphonate3 mitE-Konfiguration [R 2CO-CH=C(R 1)-P(O)(OR)2], werden in guten Ausbeuten durchWittig-Reaktion von Acylphosphonsäureestern1 [R 1CO-P(O)(OR)2,R 1=Alkyl oder Aryl] mit (2-Oxoalkyliden)triphenylphosphoranen2 [R 2CO-CH=PPh 3,R 2=Alkyl, O-Alkyl oder CH2 X (X=Br, OMe, CO2 Et)] erhalten.
A convenient route to -substituted dialkyl (E)-3-oxo-1-alkenylphosphonates
-Substituted dialkyl (E)--acylvinylphosphonates [R 2CO-CH=C(R 1)-P(O)(OR)2,3], are easily obtained in good yields byWittig-reaction of dialkyl acylphosphonates1 [R 1CO-P(O)(OR)2,R 1=alkyl or aryl) with 2-oxoalkylidene triphenylphosphoranes2 [R 2CO-CH=PPh 3,R 2=alkyl, O-alkyl and CH2 X (X=Br, OMe, CO2 Et)].
  相似文献   

14.
The C? H proton NMR spectra of the twenty conceivable methyl and ethyl substituted hydrazines are presented and analyzed with respect to effects on chemical shifts of the C? H protons caused by replacement of hydrogen by methyl and ethyl groups on the C? N? N? C chain. Thirteen different methyl substituent effects and six different ethyl substituent effects are identified and evaluated. Most of the effects are shielding and in accordance with an electron-releasing inductive effect of alkyl groups. A deshielding effect (the ‘C? C bond effect’) is observed when a methyl group replaces the hydrogen on the carbon bearing the hydrogen in focus and primary hydrogen on the carbon bearing the hydrogen in focus and primary hydrogens become secondary, as observed in other systems. On the basis of their effects on the chemical shifts of methyl protons in CH3X, eighteen different hydrazyl groups (× = ? NR1NR2R3) fall into three classes: I (R1 = H; R2, R3 = H or alkyl); II (R1 = alkyl; R2 and/or R3 = H); III (R1, R2 and R3 = alkyl), with slightly different electronegativities: 2·94, 2·83 and 2·74, respectively.  相似文献   

15.
Electron capture processes in a series of copper (II) β-diketonate complexes of formula Cu[R1COCHCOR2]2 (where R1 is an alkyl, perfluoroalkyl or aryl group and R2 either an alkyl or aryl group) have been examined. Molecular anions, ligand ions and some novel rearrangement ions have been observed with these compounds. Relative intensities of fragment ions were dependent on the substituents R1, R2 as well as the electron energy and compound pressure in the ion source. By operating the mass spectrometer at compound pressures of c. 4×10?6 Torr and higher, reproducible negative ion mass spectra (free from any significant ion-molecule contributions) have been obtained for all compounds of the series.  相似文献   

16.
Abstract

The syntheses in solution of (i) 2,4-dialkylamino-, (ii) 2,4-dimethyl-, and (iii) 2,4-diphenyl-2,4-dithio-cyclodiphosph(V)azanes, [R′P(S)NR]2 (R′ = NHR, Ph, or Me; R = alkyl), derived from thiophosphoryl trichloride, methylphosphonothioic and phenylphosphonothioic dichlorides and primary alkylamines are described. N.m.r. spectroscopic properties for these cyclodiphosph(V)azanes and their monomeric precursors, R′P(S)(NHR)2 (R′ = NHR, Ph, or Me; R = alkyl), are presented and structural inferences are drawn from this data. The X-ray crystal structure of [PhP(S)NBui]2 is reported.  相似文献   

17.
Abstract

β,γ-Unsaturated amides are versatile intermediates in the organic synthesis e.g. in the synthesis of various analogues of penicillins, cephalosporins, carbapenems, and 1) functionalized monocyclic β-lactam antibiotics. We have now developed a novel route to β,γ-unsaturated. amides 3 starting from di ethoxyphosphory l propionic acid (1). Dilithium derivative of the acid 1 reacts with a variety of carbonyl compounds to give lactons 2. Treatment of 2 with amines results in nucleophilic lacton ring opening with subsequent Horner-Emnons olefination to give 3 (R5=HI. Alkylation of the lithiated lacton 2 with alkyl halogens folloved by the ring opening-olefination sequence provides d-substituted α, -unsaturated amides 3 (R5=alkyl).  相似文献   

18.
Abstract

Four new host compounds 1–3 (a, b) derived from malic acid as different optical species and having particular lateral substituents were synthesized. Their properties in crystalline inclusion formation were studied and discussed. Crystal structures of a free host compound 1 and its ethanol inclusion complex [1·EtOH (1:1)] have been determined by X-ray analysis [1: orthorhombic, P212121, a = 9.304(3), b = 14.950(3), c = 15.712(3) Å, Dc = 1.248 Mg·m?3, Z = 4, R = 0.039 for 2474 reflexions; 1·EtOH (1:1): triclinic, P 1; a = 11.945(3), b = 14.080(3), c = 16.029(4) Å, α = 106.82(2), β = 97.74(2), γ = 89.93(2)°, Dc = 1.187 Mg·m3, Z = 4, R = 0.096 for 10404 data]. Spontaneous resolution occurs during crystallization in crystals of 1. An interesting H-bonding pattern develops that probably is responsible for the inclusion formation with ethanol in the associate crystal.  相似文献   

19.
A strong deshielding effect is observed for the carbon signal of carbocation center (C+) in the 13C NMR spectra of coordinated propargyl cations [Cp2Mo2(CO)4(μ-η23-(HC≡CCR1R2)]+ BF4 (R1 = R2 = H) 1, (R1 = Me, R2 = H) 2, and (R1 = R2 = Me) 3 when hydrogen is replaced by methyl; the effect increases with the Mo-C+ distance (75.37, 98.3, and 148.68 ppm for compounds 1, 2, and 3, respectively). This indicates that the back-donation of electron density from the metal onto the ligand makes a substantial contribution to the stabilization of these cations. Original Russian Text ? I.V. Barinov, V.A. Chertkov, 2009, published in Vestnik Moskovskogo Universiteta. Khimiya, 2009, No. 1, pp. 29–34.  相似文献   

20.
Two benzo-18-crown-6 (B18-C-6) complexes: [Na(B18-C-6)]2[Pd(SCN)4](H2O)({bf 1}) and [Na(B18-C-6)]2[Pt(SCN)4]...0.5C2H4C12 (2)have been synthesized and characterized by elemental analysis, IR spectrum and X-raydiffraction analysis. The crystal of complex 1 belongs to monoclinic, space group P21/n with cell dimensions, a = 1.0481(3), b = 1.2864 (3), c = 1.7003 (4) nm, = 93.626(4)°, V = 2.2879 (9) nm3, Z = 2, Dcalcd = 1.491 g/cm3, F(000) = 1060, R1 = 0.0562, wR2 = 0.1412 and 2 is triclinic, spacegroup P1 with cell dimensions, a = 0.9581(3), b = 1.2173 (3), = 2.1198 (6) nm, = 79.522(4), = 77.911(4), = 78.617(4)°, V = 2.3442(11) nm3 Z = 2, Dcalcd = 1.626 g/cm3, F(000) = 1154, R1 = 0.0515, wR2 = 0.0612.Two complexes show one-dimensional chain of [Na(B18-C-6)]+ complex cations and [M(SCN)4]2- (M = Pd, Pt) complex anion bridged by Na–O–Na interactions of H2O molecule or Na-O bond of B18-C-6 between adjacent [Na(B18-C-6)]+ units respectively.  相似文献   

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