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Jiang XL, Shi Y, Tian WS. Constructing 24(23→22)-abeo-Cholestane from Tigogenin in a 20(22→23)-abeo-Way via a PhI(OAc) 2-mediated Favorskii Rearrangement. J Org Chem 2017; 82:4402-4406. [PMID: 28345921 DOI: 10.1021/acs.joc.6b03043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transforming tigogenin, a steroidal sapogenin, to a 24(23→22)-abeo-cholestane, which is an unusual structural feature shared by the aglycons of saundersiosides and candicanoside A, is described. The spiroketal of tigogenin was unfolded and the resulting C22-ketone was subjected to Favorskii rearrangement mediated by PhI(OAc)2/KOH/MeOH to squeeze out the C22 from the side chain, thus reaching the 24(23→22)-abeo-cholestane structure.
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Affiliation(s)
- Xiao-Ling Jiang
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China
| | - Yong Shi
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China
| | - Wei-Sheng Tian
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China
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2
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Kuzmanich G, Spänig F, Tsai CK, Um JM, Hoekstra RM, Houk KN, Guldi DM, Garcia-Garibay MA. Oxyallyl exposed: an open-shell singlet with picosecond lifetimes in solution but persistent in crystals of a cyclobutanedione precursor. J Am Chem Soc 2011; 133:2342-5. [PMID: 21299211 DOI: 10.1021/ja109494b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoinduced decarbonylation of 2,4-bis(spirocyclohexyl)-1,3-cyclobutanedione 1 in the crystalline solid state resulted in formation of a deep blue transient with λ(max) = 550 nm and a half-life of 42 min at 298 K, identified as kinetically stabilized oxyallyl. Support for an open-shell singlet species was obtained by spectroscopic analysis and (4/4) CASSCF calculations with the 6-31+G(d) basis set and multireference MP2 corrections. The electronic spectrum of the singlet biradical, confirmed by femtosecond pump-probe studies in solution, was matched by coupled cluster calculations with single and double corrections.
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Affiliation(s)
- Gregory Kuzmanich
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1559, USA
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3
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Gomez I, Reguero M. Substituent and solvent influence on the nature of the oxyallyl intermediate in the rearrangement of bicyclo[3.1.0]hex-3-en-2-ones. Mol Phys 2007. [DOI: 10.1080/00268970500418026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- I. Gomez
- a Universitat Rovira i Virgili , Catalonia, Spain
| | - M. Reguero
- a Universitat Rovira i Virgili , Catalonia, Spain
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4
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de Meijere A, Kozhushkov SI, Yufit DS, Boese R, Haumann T, Pole DL, Sharma PK, Warkentin J. Cyclopropyl Building Blocks for Organic Synthesis, 36. Unprecedented Addition of Dialkoxycarbenes to Tetrasubstituted Alkenes: Bicyclopropylidene and 2-Chlorocyclopropylideneacetate. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/jlac.199619960421] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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5
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Sander W, Wrobel R, Komnick P, Rademacher P, Muchall HM, Quast H. Flash Vacuum Pyrolysis and Photolysis of 3,3,5,5-Tetramethylpyrazolin-4-one - A Matrix Isolation Study. European J Org Chem 2000. [DOI: 10.1002/(sici)1099-0690(200001)2000:1<91::aid-ejoc91>3.0.co;2-c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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6
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Hess, Jr. BA, Smentek L. On the Relative Stabilities of Singlet and Triplet Oxyallyl and Cyclopropanone: A Density Functional Study. European J Org Chem 1999. [DOI: 10.1002/(sici)1099-0690(199912)1999:12<3363::aid-ejoc3363>3.0.co;2-o] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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7
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Matlin AR, Lahti PM, Appella D, Straumanis A, Lin S, Patel H, Jin K, Schrieber KP, Pauls J, Raulerson P. Photoinduced Cycloaddition and Ene Reactions of 2,7-Cyclooctadienone: Experimental and Computational Studies of a Cyclopentyl Oxyallyl Intermediate. J Am Chem Soc 1999. [DOI: 10.1021/ja984128g] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Albert R. Matlin
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Paul M. Lahti
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Daniel Appella
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Andrei Straumanis
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Susanne Lin
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Hiren Patel
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Kyo Jin
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Keith P. Schrieber
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Jonathan Pauls
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
| | - Patrick Raulerson
- Contribution from the Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, and Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
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8
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Hess, BA, Eckart U, Fabian J. Rearrangements of Allene Oxide, Oxyallyl, and Cyclopropanone. J Am Chem Soc 1998. [DOI: 10.1021/ja9821652] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B. Andes Hess,
- Contribution from the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, and Institut für Organische Chemie, Technische Universität Dresden, D-01062 Dresden, Germany
| | - U. Eckart
- Contribution from the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, and Institut für Organische Chemie, Technische Universität Dresden, D-01062 Dresden, Germany
| | - J. Fabian
- Contribution from the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, and Institut für Organische Chemie, Technische Universität Dresden, D-01062 Dresden, Germany
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Schalley CA, Blanksby S, Harvey JN, Schröder D, Zummack W, Bowie JH, Schwarz H. A Combined Neutralization-Reionization Mass Spectrometric and Theoretical Study of Oxyallyl and Other Elusive [C3, H4, O] Neutrals. European J Org Chem 1998. [DOI: 10.1002/(sici)1099-0690(199806)1998:6<987::aid-ejoc987>3.0.co;2-g] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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10
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Hrovat DA, Rauk A, Sorensen TS, Powell HK, Borden WT. Ring Opening of Bicyclo[n.1.0]alkanones to 2-Cycloalkanone-1,3-diyls. Why Does Oxyallyl Diradical Formation Require Less Energy from Bicyclo[3.1.0]hexan-6-ones than from Bicyclo[1.1.0]butan-2-ones? J Am Chem Soc 1996. [DOI: 10.1021/ja954296y] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David A. Hrovat
- Contribution from the Departments of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, and University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Arvi Rauk
- Contribution from the Departments of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, and University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - T. S. Sorensen
- Contribution from the Departments of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, and University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Helen K. Powell
- Contribution from the Departments of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, and University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Weston Thatcher Borden
- Contribution from the Departments of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, and University of Calgary, Calgary, Alberta T2N 1N4, Canada
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11
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Sorensen TS, Sun F. In situ preparation of cyclopropanones with the bicyclo[3.1.0]hexan-6-one skeleton (substituted examples of the Loftfield intermediate). Confirmation of a very facile intramolecular alkyl cyclopropanone – dienol rearrangement. CAN J CHEM 1996. [DOI: 10.1139/v96-010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Four substituted bicyclo[3.1.0]hexan-6-ones (cyclopropanones) were prepared in situ, starting from the corresponding 2,6-dibromocyclohexanone and reductively removing the bromine atoms with the organometallic salt PPN+Cr(CO)4NO− The reaction is essentially instantaneous at −78 or−100 °C, and can be conveniently carried out in an NMR tube for easy characterization of the products by low-temperature 1H and 13C NMR spectroscopy. The1,5-di-tert-butyl and 1-tert-butyl analogs were thermally stable to ca. 0 °C, but the 1-tert-butyl-5-methyl and 1-tert-butyl-5-ethyl derivatives were extremely labile, rearranging at ca. −80 °C into a cross-conjugated enol, where the methyl (or ethyl) substituent was converted into an exomethylene group. These enols were also characterized as in situ species using 1H and 13C NMR spectroscopy, and by allowing the enol → α,β-unsaturated ketone rearrangement to take place at about 25 °C. The mechanism of the enol formation was investigated using a 1 -tert-butyl-5-CD3 analog, and the kH/kD ratio for enol formation was determined to be 6 ± 2. From this, the rate-determining step in the enol formation was postulated as a C-H → H-O transfer of a hydrogen atom in a cyclohexyl oxyallyl intermediate. The 1,5-di-tert-butylbicyclohexanone shows dynamic 1H NMR line broadening, the origin of which is also proposed to involve a cyclohexyl oxyallyl intermediate. Key words: cyclopropanone, oxyallyl, bicyclo[3.1.0]hexan-6-one, dienol, sigmatropic rearrangement.
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