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Artigo Revisado por pares

Charles D. Beard, Carl Djerassi, J. Sicher, Flórián Sipos, Miloš Tichý,

Optically active cis- and trans-2-methyl-4-t-butylcyclohexanone have been synthesized and equilibrated in an alkaline medium. The position of the equilibrium, as determined by optical rotatory dispersion or gas chromatographic measurements, agreed well with earlier published data in the racemic series. The optical rotatory dispersion curve of cis-2-methyl-4-butylcyclohexanone, a substance which has been used earlier to demonstrate the absence of a “2-alkyl ketone effect,” points towards a departure ...

Tópico(s): Organic Chemistry Cycloaddition Reactions

1963 - Elsevier BV | Tetrahedron

Artigo Revisado por pares

M. Tichý, Miloš Buděšı́nský, Jana Günterová, Jiřı́ Závada, Jaroslav Podlaha, Ivana Cı́sařová,

The reaction of unsubstituted as well as 6,6′-disubstituted biphenyl-2,2′-dicarboxaldehydes with HCN and ammonia or methylamine has been investigated. It has been found that the final reaction step, the addition of HCN to the intermediary cyclic imino nitriles, is a strictly diastereoselective process, yielding always only one of the two diastereoisomers of the title products, the stereoselection being controlled by the chiral twist of the biaryl axis.

Tópico(s): Asymmetric Synthesis and Catalysis

1999 - Elsevier BV | Tetrahedron

Artigo

Vladimı́r Hanuš, František Tureček, Ahmad M. Farag, Miloš Tichý,

... 6, CzechoslovakiaSearch for more papers by this authorMiloš Tichý, Miloš Tichý Institute of Organic Chemistry and Biochemistry, 166 ... 6, CzechoslovakiaSearch for more papers by this authorMiloš Tichý, Miloš Tichý Institute of Organic Chemistry and Biochemistry, 166 10 ...

Tópico(s): Molecular spectroscopy and chirality

1984 - Wiley | Organic Mass Spectrometry

Artigo Revisado por pares

Miloš Tichý, Jiří Jonáš, J. Sicher,

Tópico(s): Various Chemistry Research Topics

1959 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo

M. CHEREST, Hugh Felkin, J. Sicher, Flórián Sipos, Miloš Tichý,

M. Chérest, H. Felkin, J. Sicher, F. Šipoš and M. Tichý, J. Chem. Soc., 1965, 2513 DOI: 10.1039/JR9650002513

Tópico(s): Chemical Synthesis and Reactions

1965 - Chemical Society | Journal of the Chemical Society (Resumed)

Artigo Revisado por pares

J. Sicher, Miloš Tichý,

Tópico(s): Molecular spectroscopy and chirality

1967 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo Revisado por pares

Miloš Tichý, Flórián Sipos, J. Sicher,

Tópico(s): Molecular Spectroscopy and Structure

1966 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo Revisado por pares

Miloš Tichý,

Tópico(s): Molecular spectroscopy and chirality

1972 - Elsevier BV | Tetrahedron Letters

Artigo Revisado por pares

I. Frič, Petr Maloň, Miloš Tichý, K. Bláha,

Tópico(s): Molecular Sensors and Ion Detection

1977 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo

Pierre Longevialle, Jean‐Pierre Girard, Jean‐Claude Rossi, Miloš Tichý,

Abstract The conformer populations of conformationally mobile β‐amino alcohols in the gas phase, can be evaluated from the relative intensity of the dehydration peak [MHH 2 O] + in isobutane chemical ionization mass spectrometry.

Tópico(s): Advanced Chemical Sensor Technologies

1980 - Wiley | Organic Mass Spectrometry

Artigo

Pierre Longevialle, Jean‐Pierre Girard, Jean‐Claude Rossi, Miloš Tichý,

Abstract Dehydration of β‐amino alcohols after chemical ionization with iso‐butane as reagent gas is dependent upon the interfunctional distance. Relative protonation cross‐sections of both functional groups appear to be essentially independent of their relative proton affinities.

Tópico(s): Isotope Analysis in Ecology

1979 - Wiley | Organic Mass Spectrometry

Artigo Revisado por pares

Raymond Houriet, Hermann Ruefenacht, Pierre Alain Carrupt, Pierre Vogel, Miloš Tichý,

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSite of protonation and conformational effects on gas-phase basicity in .beta.-amino alcohols. The nature of internal hydrogen bonding in .beta.-hydroxy ammonium ionsRaymond Houriet, Hermann Ruefenacht, Pierre Alain Carrupt, Pierre Vogel, and Milos TichyCite this: J. Am. Chem. Soc. 1983, 105, 11, 3417–3422Publication Date (Print):June 1, 1983Publication History Published online1 May 2002Published inissue 1 June 1983https://pubs.acs.org/doi/10.1021/ja00349a006https:// ...

Tópico(s): Molecular spectroscopy and chirality

1983 - American Chemical Society | Journal of the American Chemical Society

Artigo

Raymond Houriet, Hermann Rufenacht, Daniel Ståhl, Miloš Tichý, Pierre Longevialle,

Abstract The gas phase protonation of β‐amino alcohols and subsequent water loss is investigated in an ion cyclotron resonance spectrometer. It is found that the loss of water is correlated with the formation of oxonium ions (OH protonation). A relationship is found between the extent of internal stabilization at short interfunctional distance in protonated amono alcohols and the exoergicity of protonation required to induce the loss of a water molecule.

Tópico(s): Advanced Chemical Sensor Technologies

1985 - Wiley | Organic Mass Spectrometry

Artigo Acesso aberto Revisado por pares

Petr Sehnal, Irena G. Stará̈, David Šaman, Miloš Tichý, Jiří Míšek, Josef Cvačka, Lubomı́r Rulı́šek, Jana Vacek Chocholoušová, Jaroslav Vacek, Grzegorz Goryl, Marek Szymoński, Ivana Cı́sařová, Ivo Starý,

Along with the recent progress in the development of advanced synthetic methods, the chemical community has witnessed an increasing interest in promising carbon-rich materials. Among them, helicenes are unique 3D aromatic systems that are inherently chiral and attractive for asymmetric catalysis, chiral recognition and material science. However, there have been only limited attempts at synthesizing long helicenes, which represent challenging targets. Here, we report on an organometallic approach ...

Tópico(s): Photochromic and Fluorescence Chemistry

2009 - National Academy of Sciences | Proceedings of the National Academy of Sciences

Artigo Revisado por pares

Jiří Míšek, Miloš Tichý, Irena G. Stará̈, Ivo Starý, Detlef Schröder,

By means of selective deuterium labeling of 1-aza[6]helicene combined with resolution of the enantiomers, chiral discrimination in silver(I)-bound dimers of the type [LAgL′] + is probed by electrospray mass spectrometry. The analysis of the results reveals a pronounced preference for the formation of homochiral dimers ( P , P and M , M , respectively) over the statistically preferred heterochiral variant ( P , M ), which is fully consistent with previous data about the formation of homochiral dimers in the condensed ...

Tópico(s): Mass Spectrometry Techniques and Applications

2009 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo Revisado por pares

Irena G. Stará̈, Ivo Starý, Miloš Tichý, Jiřı́ Závada, Pavel Fiedler,

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNucleophilic Attack on 4,5-Dihydro-4-alkyl-3H-dinaphtho[2,1-c:1',2'-e]thiepinium Salts. A Convenient Approach to New 2,2'-Bidentate 1,1'-Binaphthalene Ligands with Sulfur Donor AtomsIrena G. Stara, Ivo Stary, Milos Tichy, Jiri Zavada, and Pavel FiedlerCite this: J. Org. Chem. 1994, 59, 6, 1326–1332Publication Date (Print):March 1, 1994Publication History Published online1 May 2002Published inissue 1 March 1994https://doi.org/10.1021/jo00085a021RIGHTS & PERMISSIONSArticle ...

Tópico(s): Synthesis and biological activity

1994 - American Chemical Society | The Journal of Organic Chemistry

Artigo

Christian Lohfink, H. Baecker, Miloš Tichý,

Tópico(s): Combustion and flame dynamics

2008 - | SAE technical papers on CD-ROM/SAE technical paper series

Artigo Revisado por pares

Jiří Míšek, Filip Teplý, Irena G. Stará̈, Miloš Tichý, David Šaman, Ivana Cı́sařová, P. Vojtíšek, Ivo Starý,

Silberschrauben: Eine Cobalt(I)-katalysierte Triin-Cyclotrimerisierung mit anschließender Aromatisierung durch MnO2 unter Mikrowellenbestrahlung schließt eine praktische Synthese von Diaza[5]helicenen und Aza[6]helicenen ab. Die Aza[6]helicen-Enantiomere wurden getrennt, die Energiebarriere für die Racemisierung bestimmt und Röntgenstrukturanalysen an Silberkomplexen ausgeführt (siehe Bild; Cp = C5H5, OTf = Triflat).

Tópico(s): Origins and Evolution of Life

2008 - Wiley | Angewandte Chemie

Artigo Revisado por pares

Luděk Ridvan, N. A. ABDALLAH, Roman Holakovský, Miloš Tichý, Jiřı́ Závada,

The title compound 4, possessing a biaryl axis as the sole source of chirality, has been prepared in the enantiomerically pure (R) as well as racemic form by two alternative procedures starting from dibromide 1.

Tópico(s): Chemical Synthesis and Analysis

1996 - Elsevier BV | Tetrahedron Asymmetry

Artigo Revisado por pares

Miloš Tichý, Jiřı́ Závada, Jaroslav Podlaha, P. Vojtíšek,

Tópico(s): Mass Spectrometry Techniques and Applications

1995 - Elsevier BV | Tetrahedron Asymmetry

Artigo Revisado por pares

L. Lindborg, D. T. Bartlett, P. Drake, Herbert A. Klein, Th. Schmitz, Miloš Tichý,

The accuracy of the dosimetry (personal and area monitoring) has been investigated inside the containment buildings of two pressurised water reactors and in the environment of a transport cask with spent fuel elements. The dosimetric quantities of main interest were ambient dose equivalent and personal dose equivalent, as operational quantities, and effective dose equivalent, as limit quantity. They were either directly determined by means of instruments and dosemeters or calculated from the experimentally ...

Tópico(s): Nuclear reactor physics and engineering

1995 - Oxford University Press | Radiation Protection Dosimetry

Artigo Revisado por pares

Miloš Tichý, Jana Holanová, Jiřı́ Závada,

The optically active amino acids (R)-7 and (S)-8 were prepared as the first representatives of ω-amino acids possessing a biaryl axis as the sole element of chirality.

Tópico(s): Chemical Synthesis and Analysis

1998 - Elsevier BV | Tetrahedron Asymmetry

Artigo Revisado por pares

Miloš Tichý, Jana Holanová, Jiřı́ Závada,

(R)-(+)-6,6′-Dinitrobiphenyl-2,2′-dicarboxylic acid, ionically bonded to 3-aminopropylsilanized silica (CSP 1), is the first ionically bonded axially chiral phase of C2 symmetry. The phase is specifically efficient for the separation of a wide range of enantiomeric vicinal benzamido alcohols, whether open-chain, cyclic or polycyclic. To assess the steric and polar effects of the 6,6′-substituents, the performance of CSP 1 is compared with that of the analogous (but less effective) phase CSP 2, based ...

Tópico(s): Mass Spectrometry Techniques and Applications

1994 - Elsevier BV | Journal of Chromatography A

Artigo Revisado por pares

Luděk Ridvan, Miloš Buděšı́nský, Miloš Tichý, Petr Maloň, Jiřı́ Závada, Jaroslav Podlaha, Ivana Cı́sařová,

Abstract Conversion of the easily accessible racemic bis(amino acid)s cis- and trans-2a into the (S)-enantiomers via the corresponding Schiff bases with (1S,2S,5S)-2-hydroxy-3-pinanone is described. Condensation of the N-Boc-protected bis(amino acid)s with esters of the corresponding axially chiral amino acids (R)- and (S)- 1b afforded tetraspiro-substituted bis(dioxopiperazine)s 7 representing a rare case of primary helical topology. Absolute configuration of the products was assigned by NMR and CD ...

Tópico(s): Chemical Synthesis and Analysis

1999 - Elsevier BV | Tetrahedron

Artigo Revisado por pares

Miloš Tichý,

The conditional probability theorem was used for the inference of the a posteriori distribution of neutron spectra and cross sections from integral detector data. The normal probability distribution was chosen for both the a priori distribution of the flux and the distribution of measured activities. The covariance filter was used in the BASACF program written for the calculation of the a posteriori distribution parameters flux and cross sections and consequently for the calculation of the mean ...

Tópico(s): Radiation Detection and Scintillator Technologies

1988 - Elsevier BV | Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment

Artigo Revisado por pares

Miloš Tichý, Petr Maloň, I. Frič, K. Bláha,

Tópico(s): Structural and Chemical Analysis of Organic and Inorganic Compounds

1977 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo Revisado por pares

K. Bláha, Petr Maloň, Miloš Tichý, I. Frič, Ramakrishnan Usha, Suryanarayana Rao Ramakumar, Kailasam Venkatesan,

Tópico(s): Molecular Sensors and Ion Detection

1978 - Wiley-VCH | Collection of Czechoslovak Chemical Communications

Artigo Revisado por pares

Miloš Tichý, Tomáš Kraus, Jiřı́ Závada, Ivana Cı́sařová, Jaroslav Podlaha,

Abstract The title (R)-diacid has been found to self-assemble as hydrogen-bonded cyclotetramers in solution as well as in the solid phase; in the crystal the tetramers are stacked into chiral columns. In contrast, the racemic diacid forms infinite zig-zag chains of molecules of alternating chirality.

Tópico(s): Surface Chemistry and Catalysis

1999 - Elsevier BV | Tetrahedron Asymmetry