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Resendiz MJE, Taing J, Garcia-Garibay MA. Photodecarbonylation of 1,3-Dithiophenyl Propanone: Using Nanocrystals to Overcome the Filtering Effect of Highly Absorbing Trace Impurities. Org Lett 2007; 9:4351-4. [PMID: 17877364 DOI: 10.1021/ol702000s] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Irradiation of crystalline 2,4-dimethyl-2,4-di(thiophen-3-yl)pentan-3-one (1) resulted in photodecarbonylation and radical combination to give 2 with >99% selectivity. However, extended irradiation led to no more than ca. 8% conversion due to highly absorbing unidentified trace impurities that act as filters. We report here a simple procedure to improve the reaction efficiency by taking advantage of nanocrystalline suspensions prepared by the reprecipitation method, which leads to shorter reaction times and quantitative yields.
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Affiliation(s)
- Marino J E Resendiz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
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2
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Takahashi O, Yamasaki K, Kohno Y, Ueda K, Suezawa H, Nishio M. Origin of the π-Facial Stereoselectivity in the Addition of Nucleophilic Reagents to Chiral Aliphatic Ketones as Evidenced by High-Level Ab Initio Molecular-Orbital Calculations. Chem Asian J 2006; 1:852-9. [PMID: 17441128 DOI: 10.1002/asia.200600204] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Ab initio molecular-orbital (MO) calculations were carried out, at the MP2/6-311++G(d,p)//MP2/6-31G(d) level, to investigate the conformational Gibbs energy of alkyl 1-cyclohexylethyl ketones, cyclo-C6H11CHCH3-CO-R (R = Me, Et, iPr, and tBu). In each case, one of the equatorial conformations was shown to be the most stable. Conformers with the axial CHCH3COR group were also shown to be present in an appreciable concentration. Short C-H...C=O and C-H...O=C distances were found in each stable conformation. The result was interpreted on the grounds of C-H...pi(C=O) and C-H...O hydrogen bonds, which stabilize the geometry of the molecule. The ratio of the diastereomeric secondary alcohols produced in the nucleophilic addition to cyclo-C6H11CHCH3-CO-R was estimated on the basis of the conformer distribution. The calculated result was consistent with the experimental data previously reported: the gradual increase in the product ratio (major/minor) along the series was followed by a drop at R = tBu. The energy of the diastereomeric transition states in the addition of LiH to cyclo-C6H11CHCH3-CO-R was also calculated for R = Me and tBu. The product ratio did not differ significantly in going from R = Me to tBu in the case of the aliphatic ketones. This is compatible with the above result calculated on the basis of the conformer distribution. Thus, the mechanism of the pi-facial selection can be explained in terms of the simple premise that the geometry of the transition state resembles the ground-state conformation of the substrates and that the nucleophilic reagent approaches from the less-hindered side of the carbonyl pi face.
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Affiliation(s)
- Osamu Takahashi
- Department of Chemistry, Graduate School of Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
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Resendiz MJE, Garcia-Garibay MA. Hammett Analysis of Photodecarbonylation in Crystalline 1,3-Diarylacetones. Org Lett 2005; 7:371-4. [PMID: 15673242 DOI: 10.1021/ol0480527] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The relative quantum yields and chemical efficiencies of crystalline p,p'-disubstituted 1,3-diphenyl-2-propanones with 4-MeO, 4-Me, 4-F, 4-CF3, and 3,4-diMeO groups were determined by parallel irradiation of polycrystalline samples. Variations in quantum yields that span a factor of 4 are analyzed in terms of the effects of substituents on the stability of the benzylic radical. All solid-state reactions proceeded with 100% chemoselectivity and in >95% chemical yield.
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Affiliation(s)
- Marino J E Resendiz
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095-1569, USA
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4
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Langley CH, Lii JH, Allinger NL. Molecular mechanics (MM4) calculations on carbonyl compounds part I: aldehydes. J Comput Chem 2001. [DOI: 10.1002/jcc.1098] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Langley CH, Lii JH, Allinger NL. Molecular mechanics calculations on carbonyl compounds. II. Open-chain ketones. J Comput Chem 2001. [DOI: 10.1002/jcc.1099] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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6
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Metha GF, Buntine MA, Bradley AJ, Morrison RJS. Jet-Cooled Multiphoton Ionization Spectroscopy of the iso-Butanal 3s<--n Rydberg Transition. JOURNAL OF MOLECULAR SPECTROSCOPY 2001; 206:73-82. [PMID: 11281687 DOI: 10.1006/jmsp.2000.8293] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report the results of a study on the vibrational structure in the (n, 3s) Rydberg state of iso-butanal, carried out via 2+1 multiphoton ionization spectroscopy in a supersonic expansion. Spectra were recorded for both the normal species, (CH(3))(2)CHCHO, and the deuterated isotopomer, (CH(3))(2)CDCHO. The spectra show a complicated vibrational pattern attributable to the gauche (C(1)) conformer which is known to be 250 cm(-1) lower in energy than the more symmetric trans (C(s)) conformer. The spectra are dominated by the low-frequency formyl torsion which appears in combination with the two methyl torsions (in-phase and out-of-phase) and with several skeletal modes. Vibrational assignments have been aided by ab initio calculations of the (n, 3s) Rydberg state. Copyright 2001 Academic Press.
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Affiliation(s)
- G. F. Metha
- Department of Chemistry, University of Adelaide, Adelaide, South Australia, 5005, Australia
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Garcia-Garibay MA, Shin S, Sanrame CN. Engineering Reactions in Crystalline Solids: Prediction of Intramolecular Carbene Rearrangements. Tetrahedron 2000. [DOI: 10.1016/s0040-4020(00)00495-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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8
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Affiliation(s)
- Allan D. Headley
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409‐1061
| | - Stephen D. Starnes
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409‐1061
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Durig JR, Guirgis GA, Bell S, Brewer WE. Far-Infrared Spectrum, ab Initio Calculations, Conformational Energy Differences, Barriers to Internal Rotation, and r0 Structure of Propanal. J Phys Chem A 1997. [DOI: 10.1021/jp971106s] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. R. Durig
- Department of Chemistry, University of MissouriKansas City, Kansas City, Missouri 64110, Department of Chemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K., and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Gamil A. Guirgis
- Department of Chemistry, University of MissouriKansas City, Kansas City, Missouri 64110, Department of Chemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K., and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - Stephen Bell
- Department of Chemistry, University of MissouriKansas City, Kansas City, Missouri 64110, Department of Chemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K., and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
| | - W. E. Brewer
- Department of Chemistry, University of MissouriKansas City, Kansas City, Missouri 64110, Department of Chemistry, University of Dundee, Dundee DD1 4HN, Scotland, U.K., and Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
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Lecea B, Arrieta A, Cossío FP. Solvent Effects on the Conformer Distribution of 2-Methoxypropanal and Chloroacetaldehyde. A Model Case for the Conformational Analysis in Solution of Chiral Aldehydes Including Polar Groups. J Org Chem 1997. [DOI: 10.1021/jo970468t] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Begoña Lecea
- Farmazi Fakultatea, Euskal Herriko Unibertsitatea, P.K. 450, 01080 Vitoria-Gasteiz, Spain, and Kimika Fakultatea, Euskal Herriko Unibertsitatea, P.K. 1072, 20080 San Sebastián-Donostia, Spain
| | - Ana Arrieta
- Farmazi Fakultatea, Euskal Herriko Unibertsitatea, P.K. 450, 01080 Vitoria-Gasteiz, Spain, and Kimika Fakultatea, Euskal Herriko Unibertsitatea, P.K. 1072, 20080 San Sebastián-Donostia, Spain
| | - Fernando P. Cossío
- Farmazi Fakultatea, Euskal Herriko Unibertsitatea, P.K. 450, 01080 Vitoria-Gasteiz, Spain, and Kimika Fakultatea, Euskal Herriko Unibertsitatea, P.K. 1072, 20080 San Sebastián-Donostia, Spain
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Shin SH, Cizmeciyan D, Keating AE, Khan SI, Garcia-Garibay MA. Control of Carbene Reactivity by Crystals. A Highly Selective 1,2-H Shift in the Solid-to-Solid Reaction of 1-(4‘-Biphenylyl)-2-phenyldiazopropane to (Z)-1-(4‘-Biphenylyl)-2-phenylpropene. J Am Chem Soc 1997. [DOI: 10.1021/ja9633225] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Steve H. Shin
- Contribution from the Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Deniz Cizmeciyan
- Contribution from the Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Amy E. Keating
- Contribution from the Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Saeed I. Khan
- Contribution from the Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Miguel A. Garcia-Garibay
- Contribution from the Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
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13
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Conformational analysis of N-methylglycine and N,N-dimethylglycine by ab initio calculations. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0166-1280(96)04732-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Kang YK, No KT, Scheraga HA. Intrinsic Torsional Potential Parameters for Conformational Analysis of Peptides and Proteins. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp9611434] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Young Kee Kang
- Department of Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea, Department of Chemistry, Soong Sil University, Sang Do 5 Dong 1-1, Dong Jak Gu, Seoul 156-743, Korea, and Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301
| | - Kyoung Tai No
- Department of Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea, Department of Chemistry, Soong Sil University, Sang Do 5 Dong 1-1, Dong Jak Gu, Seoul 156-743, Korea, and Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301
| | - Harold A. Scheraga
- Department of Chemistry, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea, Department of Chemistry, Soong Sil University, Sang Do 5 Dong 1-1, Dong Jak Gu, Seoul 156-743, Korea, and Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301
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Maxwell DS, Tirado-Rives J, Jorgensen WL. A comprehensive study of the rotational energy profiles of organic systems byab initio MO theory, forming a basis for peptide torsional parameters. J Comput Chem 1995. [DOI: 10.1002/jcc.540160807] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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16
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Hernandez V, Lopez Navarrete JT. Ab initio study of torsional potentials in 2,2’‐bithiophene and 3,4’‐ and 3,3’‐dimethyl‐2,2’‐bithiophene as models of the backbone flexibility in polythiophene and poly(3‐methylthiophene). J Chem Phys 1994. [DOI: 10.1063/1.467762] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Basis set effects on the intermolecular interaction of hydrocarbon molecules obtained by an ab initio molecular orbital method: evaluation of dispersion energy. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0166-1280(94)80122-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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18
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Cossé-Barbi A, Massat A. Conformational identity change of 3-methylbutanone from gaseous phase to solutions: An IR vibrational spectroscopy study. Struct Chem 1994. [DOI: 10.1007/bf02278693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Basis set effects on the intermolecular interaction of the H2-H2 system obtained using ab initio molecular orbital calculations with the Møller-Plesset perturbation correction. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0166-1280(93)80014-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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20
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Durig J, Guirgis G, Brewer W, Little T. Vibrational spectra and structure, ab initio calculations, and conformational stability of 2-methylpropanal. J Mol Struct 1991. [DOI: 10.1016/0022-2860(91)85003-l] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Chung-Phillips A, Stevenson TA. Simulations of internal rotation potential energies for substituted ethanes. J Comput Chem 1990. [DOI: 10.1002/jcc.540110607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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