Synthesis and characterization of 1-methyl-1-silaindane and 1-methyl-1-germaindane

New synthetic routes to 1-methyl-1-silaindane (1b) and 1-methyl-1-germaindane (1b) were developed and the desired products were obtained in good isolated yield. Compounds 1a and 1b were fully characterized by mass spectroscopy, ¹H and ¹³C{¹H} NMR, and infrared spectroscopy.     

Regio and stereoselective synthesis of 1-methylseleno-1-vinyl and 1-phenylseleno-1-vinyl cyclopropanes

The Z and E teomers of the title compounds are regioselectivity and stereoselectively prepared respectively by reaction of phosphorus ylides with α-selenocyclopropyl aldehydes and by addition of α-lithio seleno-cyclopropanes on α-seleno aldehydes.     

2 1 1At-tellurium colloid and Na2 1 1At injections,and their radiobiological effects

Na^{2 1 1}At and^{2 1 1}At–Te colloid injections were prepared. By comparison with tissue distribution of Na^{2 1 1}At and^{2 1 1}At–Te colloid injections it has been demonstrated that the^{2 1 1}At–Te colloid is stable in vivo. It has been shown that the radiohalogen,^{2 1 1}At, has huge and extensive radiobiological effects in studying on the changes in histopathology, enzyme histochemistry, chromosome aberration, micronucleus frequency of bone-marrow polychromatic erythrocytes and the injury effect of^{2 1 1}At on experimental Ehrlich ascites cells.     

Synthesis and NMR analysis of 2,4-dichloro-1-pentene and of 2,4-dichloro-1-pentene-1-d1

The compound 2,4-dichloro-1-pentene-1-d₁ ( 1 ) was synthesized starting from and CH?CNa. In the last stage of the synthesis on activated carbon-HgCl₂ catalyst), ( 3 ) were formed together with ( 1 ). The NMR parameters of ( 1 ), its cis and trans isomers and ( 2 ) were obtained in C₆D₆ solution at 100 MHz. Theoretical spectra of ( 1 ) at 60 MHz were simulated with the aid of a computer, using as input the NMR parameters obtained at 100 MHz and good agreement with the experiment was obtained.     

Electronic, vibrational, and rotational structures in the S0 1A1 and S1 1A1 states of phenanthrene

Electronic and vibrational structures in the S(0) (1)A(1) and S(1) (1)A(1) states of jet-cooled phenanthrene-h(10) and phenanthrene-d(10) were analyzed by high-resolution spectroscopy using a tunable nanosecond pulsed laser. The normal vibrational energies and molecular structures were estimated by ab initio calculations with geometry optimization in order to carry out a normal-mode analysis of observed vibronic bands. The rotational structure was analyzed by ultrahigh-resolution spectroscopy using a continuous-wave single-mode laser. It has been demonstrated that the stable geometrical structure is markedly changed upon the S(1) ← S(0) electronic excitation. Nonradiative internal conversion in the S(1) state is expected to be enhanced by this structural change. The observed fluorescence lifetime has been found to be much shorter than the calculated radiative lifetime, indicating that the fluorescence quantum yield is low. The lifetime of phenanthrene-d(10) is longer than that of phenanthrene-h(10) (normal deuterium effect). This fact is in contrast with anthracene, which is a structural isomer of phenanthrene. The lifetime at the S(1) zero-vibrational level of anthracene-d(10) is much shorter than that of anthracene-h(10) (inverse deuterium effect). In phenanthrene, the lifetime becomes monotonically shorter as the vibrational energy increases for both isotopical molecules without marked vibrational dependence. The vibrational structure of the S(0) state is considered to be homogeneous and quasi-continuous (statistical limit) in the S(1) energy region.     

1-乙酰胺基丙叉-1,1-二膦酸和1-丙酰胺基乙叉-1,1-二膦酸与碱土金属离子的螯合作用

用pH电位法研究了1-乙酰胺基丙叉-1,1-二膦酸(S-186)和1-丙酰胺基乙叉-1,1-二膦酸(S-106)与碱土金属的螯合作用(30±O.1℃).当金属离子与配体的摩尔浓度比为10∶1、1∶1和1∶2时,在水溶液中形成了MHL、ML、ML_2和M_2L等几种类型的配合物.分别测定了它们的稳定常数,其中S-186配合物稍高于S-106,说明配合物稳定性与螯合剂的碱度有平行关系.值得注意的是,这两种螯合剂与Sr~(2 )形成的双核配合物的稳定性均较其它碱土金属离子的为高.     

The mechanism of thermal dehydrochlorination. Pyrolysis of 1-Chloro-1-fluoroethane and 1-chloro-1, 1-difluoroethane

The thermal decompositions of 1-chloro-1-fluoroethane and 1-chloro-1,1-difluorethane at atmospheric pressure have been studied in the temperature range 500–600°C in a flow system. The dehydrochlorinations are homogenous in a carbonaceous reactor and unimolecular. The rate constants are given by and The criteria for molecular or chain processes in thermal dehydrochlorinations are discussed.     

Synthesis of Ethyl 1-Phenyl- and 1-Alkyl-1-Indene-2-Carboxylates

The ethyl 1-phenyl and 1-alkyl-1-indene-2-carboxylates 2g and 2a-2f respectively were prepared in 68 - 83% yield by the reaction of phenyl- and alkylmagnesium halides with ethyl 1-methoxy-1-indene-2-carboxylate (1c).     

Electrophilic condensation of 1-hydroperfluoropropylene and 1-hydroperfluoro-1-butene with fluoroethylenes

Conclusions 1-Hydroperfluoropropylene reacts with tetrafluoroethylene in the presence of SbF₅ to form the corresponding 11 and 12 adduct olefins. The condensation is accomplished at both the CFH and CF₂ groups of the starting propylene. Under analogous conditions, 1-hydroperfluoro-1-butene condenses with fluoroethylenes exclusively at the CFH group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1591–1594, July, 1982.     

Synthesis of 1-mono- and 1,2-bisacylpyrazolidines and 1-arylsulfonylpyrazolines

Study of a reaction of 1,5-diazabicyclo[3.1.0]hexanes with acyl and sulfonyl chlorides in organic or aqueous organic media in the presence of inorganic bases resulted in development of new simple one-step methods for the preparation of 1-mono- and 1,2-bisacylpyrazolidines and 1-arylsulfonylpyrazolines.     

Gas permeation properties of blend and copolymer membranes composed of 1-trimethylsilyl-1-propyne and 1-phenyl-1-propyne structures

The poly(1-trimethylsilyl-1-propyne) (PMSP) has the potential to be an important membrane gas separation material due to the fact that it has the highest gas permeability of all polymeric membranes. One problem with PMSP is a decrease in the gas permeability with age. In order to understand the aging processes, we studied the change in free volume and the molecular motions of the PMSP and its membranes modified with 1-phenyl-1-propyne (PP) structures; that is, a copolymer and a blend of PMSP and PPP. During aging, the unrelaxed volume of the PMSP membrane was relaxed, and the molecular motion of carbons dropped, suggesting that the decrease in the microvoids caused a tighter chain packing. The copolymer and blend membrane had stable permeability compared to the PMSP. In particular, the addition of a small amount of the PP structure provided excellent stability with high gas permeability. A decrease in the unrelaxed volume of modified membranes was hardly observed with age; however, the molecular motion of some carbons slightly changed. This change did not affect the gas permeability. In this case, a larger unrelaxed volume was probably a dominant factor in the gas permeation of the PMSP rich membranes relative to the molecular motion in the T₁ measurement. © 1997 John Wiley & Sons, Inc.     

Synthesis of combretastatins A-1 and B-1

Combretastatins A-1 and B-1 have been synthesized by coupling MOM-protected p-iodomethoxycatechol with 3,4,5-trimethoxyphenylacetylene in a Sonogashira reaction.     

Synthesis of substituted 1-isopropenyl- and 1-alkylbenzimidazolones

1-Isopropenylbenzimidazolones, the alkylation of which with alkyl halides and γ-butyrolactone proceeds in the 3 position, were obtained by reaction of o-phenylenediamine and its aromatic ring-substituted derivatives with acetoacetic ester.     

Synthesis and psychotropic properties of 1-triorganylsiloxy- and 1-triorganylgermoxy-germatranes

Triorganylsiloxy- and triorganylgermoxy-germatranes have been prepared by the interaction of the easily available 1-hydroxygermatrane with various hetaryl-silanes and -germanes. The compounds were of the general structure:

• M = Si; X = S, CH = CH (viz. phenyl); n = 0,1,2
• M = Ge; X = CH = CH (viz. phenyl); n = 0

All siloxy- and germoxy-germatranes obtained were subjected to psychotropic assays. Some of phenylsiloxygermatranes are effective for memory enhancement (inhibition of retrogradal amnesia by triphenylsiloxygermatrane was 80%).     

Synthesis of 1-acrylyl- and 1-methacrylyl-substituted pyrazolines and pyrazoles

1-Acrylyl- and 1-methacrylyl-substituted 3-methylpyrazolines, 3,5, 5-trimethylpyrazolines, 3-methyl-5-phenylpyrazolmes, 3-methyl-5-phenylpyrazoles, and 3,5-dimethylpyrazoles have been synthesized.     

1-Phospha- and 1-Aza-3-Phosphaallylic Anions

Abstract

Synthesis, structure and reactivity of 1-phospha- and 1-aza-3-phosphaallyl anions are discussed.