메뉴 건너뛰기




Volumn , Issue 10, 2011, Pages 1896-1913

Tandem 1,5-hydride shift/6π electrocyclization of ketenimines and carbodiimides substituted with cyclic acetal and dithioacetal functions: Experiments and computations

Author keywords

Cyclization; Density functional calculations; Hydricity; Hydride shift; Ketenimines; Reaction mechanisms

Indexed keywords


EID: 79952946673     PISSN: 1434193X     EISSN: 10990690     Source Type: Journal    
DOI: 10.1002/ejoc.201001372     Document Type: Article
Times cited : (47)

References (140)
  • 1
    • 79952941590 scopus 로고    scopus 로고
    • For some representative examples, see
    • For some representative examples, see
  • 22
    • 0000516387 scopus 로고
    • A. L. J. Beckwith
    • A. L. J. Beckwith, C. J. Easton, J. Am. Chem. Soc. 1981, 103, 615-619.
    • (1981) J. Am. Chem. Soc. , vol.103 , pp. 615-619
    • Easton, C.J.1
  • 26
    • 79952947418 scopus 로고    scopus 로고
    • For reviews in the chemistry of ketenimines, see
    • For reviews in the chemistry of ketenimines, see
  • 39
    • 0027504073 scopus 로고
    • For articles dealing with [1,3] migrations in ketenimines, see
    • U. Nubbemeyer, Synthesis 1993, 1120-1128. For articles dealing with [1,3] migrations in ketenimines, see
    • (1993) Synthesis , pp. 1120-1128
    • Nubbemeyer, U.1
  • 58
    • 79952964953 scopus 로고    scopus 로고
    • Comparable [1,5]-H shifts to central carbon atoms in allene fragments are known to occur with relative ease, see for instance
    • Comparable [1,5]-H shifts to central carbon atoms in allene fragments are known to occur with relative ease, see for instance
  • 62
    • 79952939379 scopus 로고    scopus 로고
    • For the method of preparation of compounds 4, 7, 8, 24b - e, 24g and 24h and their analytical and spectroscopic data see ref. [4a]
    • For the method of preparation of compounds 4, 7, 8, 24b-e, 24g and 24h and their analytical and spectroscopic data see ref. [4a].
  • 65
    • 79952950364 scopus 로고    scopus 로고
    • For reviews on carbodiimide chemistry, see
    • For reviews on carbodiimide chemistry, see
  • 70
    • 79952973506 scopus 로고    scopus 로고
    • For some examples of metal-catalysed carbodiimide metathesis see
    • For some examples of metal-catalysed carbodiimide metathesis see
  • 73
    • 17644404373 scopus 로고    scopus 로고
    • references therein
    • J. Louie, Curr. Org. Chem. 2005, 9, 605-623, and references therein.
    • (2005) Curr. Org. Chem. , vol.9 , pp. 605-623
    • Louie, J.1
  • 77
    • 79952915728 scopus 로고    scopus 로고
    • The structure of the pyrazolo-pyridone 35 was unequivocally determined by X-ray analysis, although the collected data are of low quality for publication. Its analytical and spectroscopic data are in full agreement with such structure
    • The structure of the pyrazolo-pyridone 35 was unequivocally determined by X-ray analysis, although the collected data are of low quality for publication. Its analytical and spectroscopic data are in full agreement with such structure.
  • 78
    • 79952945818 scopus 로고    scopus 로고
    • Note that the 1,3-dioxolane-ketenimine 37b appears in the experimental study numbered as 1a, but for the sake of avoiding confusion we have used a different numeration in the computational section
    • Note that the 1,3-dioxolane-ketenimine 37b appears in the experimental study numbered as 1a, but for the sake of avoiding confusion we have used a different numeration in the computational section.
  • 79
    • 79952913531 scopus 로고    scopus 로고
    • -1
    • -1.
  • 80
    • 79952933092 scopus 로고    scopus 로고
    • The energy barriers are relative to the most stable conformers of the reactant heterocumulenes and of the o-azaxylylene intermediates
    • The energy barriers are relative to the most stable conformers of the reactant heterocumulenes and of the o-azaxylylene intermediates.
  • 81
    • 79952926204 scopus 로고    scopus 로고
    • We have recently reported similar electrocyclic ring closures and characterized the corresponding transition states as pseudopericyclic; see reference 1n and references cited herein
    • We have recently reported similar electrocyclic ring closures and characterized the corresponding transition states as pseudopericyclic; see reference 1n and references cited herein.
  • 82
    • 79952907301 scopus 로고    scopus 로고
    • The energy of the LUMO orbital of the ketenimine is lower than that of the carbodiimide; consequently, the donor-acceptor interaction between a migrating hydride and the LUMO orbital of a heterocumulenic acceptor is more favourable in a ketenimine than in a carbodiimide
    • The energy of the LUMO orbital of the ketenimine is lower than that of the carbodiimide; consequently, the donor-acceptor interaction between a migrating hydride and the LUMO orbital of a heterocumulenic acceptor is more favourable in a ketenimine than in a carbodiimide.
  • 83
    • 79952969151 scopus 로고
    • It is known that conjugating substituents produce large accelerations of the rate of nucleophilic additions to heterocumulenes such as ketenes, see: T. T. Tidwell (Ed.), John Wiley & Sons, New York, p. 581
    • It is known that conjugating substituents produce large accelerations of the rate of nucleophilic additions to heterocumulenes such as ketenes, see: T. T. Tidwell (Ed.), Ketenes, John Wiley & Sons, New York, 1995, p. 581.
    • (1995) Ketenes
  • 91
    • 79952954351 scopus 로고    scopus 로고
    • Many H shifts have been classified as "hydride shifts". For a review on hydride shifts and transfers, see
    • Many H shifts have been classified as "hydride shifts". For a review on hydride shifts and transfers, see
  • 92
    • 0002680167 scopus 로고
    • For some representative recent examples, see
    • C. I. F. Watt, Adv. Phys. Org. Chem. 1988, 24, 57-112. For some representative recent examples, see
    • (1988) Adv. Phys. Org. Chem. , vol.24 , pp. 57-112
    • Watt, C.I.F.1
  • 108
    • 0000334295 scopus 로고    scopus 로고
    • I.-S. H. Lee
    • I.-S. H. Lee, E. H. Jeoung, J. Org. Chem. 1998, 63, 7275-7279.
    • (1998) J. Org. Chem. , vol.63 , pp. 7275-7279
    • Jeoung, E.H.1
  • 110
    • 0003446628 scopus 로고    scopus 로고
    • referentes cited therein
    • P. Brunet, J. D. Wuest, J. Org. Chem. 1996, 61, 2020-2026, and referentes cited therein.
    • (1996) J. Org. Chem. , vol.61 , pp. 2020-2026
    • Brunet, P.1    Wuest, J.D.2
  • 111
    • 0000613958 scopus 로고
    • Exceptionally, the cationic polymerization of cyclic acetals has been proposed to be initiated by a hydride transfer step from the acetal to the cationic initiator, see:, and references cited therein
    • Exceptionally, the cationic polymerization of cyclic acetals has been proposed to be initiated by a hydride transfer step from the acetal to the cationic initiator, see:, S. Penczek, Makromol. Chem. 1974, 175, 1217-1252, and references cited therein.
    • (1974) Makromol. Chem. , vol.175 , pp. 1217-1252
    • Penczek, S.1
  • 112
    • 0034733128 scopus 로고    scopus 로고
    • C-H interactions involving lone pairs at oxygen atoms are stronger than those involving sulfur atoms in analogous compounds. See:, and references cited therein
    • C-H interactions involving lone pairs at oxygen atoms are stronger than those involving sulfur atoms in analogous compounds. See:, I. V. Alabugin, J. Org. Chem. 2000, 65, 3910-3919, and references cited therein.
    • (2000) J. Org. Chem. , vol.65 , pp. 3910-3919
    • Alabugin, I.V.1
  • 113
    • 0042616101 scopus 로고
    • in:, Allenes and Related Compounds (Ed.:, Wiley-Interscience, Chichester, UK, part 2, p. 701
    • M. W. Barker, W. E. McHenry, in: The Chemistry of Ketenes, Allenes and Related Compounds (Ed.:, S. Patai), Wiley-Interscience, Chichester, UK, 1980, part 2, p. 701.
    • (1980) The Chemistry of Ketenes
    • Barker, M.W.1    McHenry, W.E.2    Patai, S.3
  • 114
    • 79952909953 scopus 로고    scopus 로고
    • Only in the case of TS2b did IRC calculation establish the connection of this transition structure with a rotational isomer, higher in energy that INTb, showing s-cis geometry around the C1-N3 bond. Consequently, the intermediate INTb, formed after the [1,5]-H shift step, should experience rotation around that bond before the electrocyclization step through a rotational transition structure that we have not optimized
    • Only in the case of TS2b did IRC calculation establish the connection of this transition structure with a rotational isomer, higher in energy that INTb, showing s-cis geometry around the C1-N3 bond. Consequently, the intermediate INTb, formed after the [1,5]-H shift step, should experience rotation around that bond before the electrocyclization step through a rotational transition structure that we have not optimized.
  • 115
    • 79952906877 scopus 로고    scopus 로고
    • In the transition states TS2b and TS2i these analyses point toward a conrotatory ring closure, possibly due to the steric requirements imposed by the two phenyl rings at the C2 atom and the acetal function at the other end. We are currently conducting a further study of these rare electrocyclizations
    • In the transition states TS2b and TS2i these analyses point toward a conrotatory ring closure, possibly due to the steric requirements imposed by the two phenyl rings at the C2 atom and the acetal function at the other end. We are currently conducting a further study of these rare electrocyclizations.
  • 133
    • 0345042108 scopus 로고
    • P. v. R. Schleyer
    • A. E. Reed, P. v. R. Schleyer, J. Am. Chem. Soc. 1990, 112, 1434-1445.
    • (1990) J. Am. Chem. Soc. , vol.112 , pp. 1434-1445
    • Reed, A.E.1
  • 136
    • 79952934267 scopus 로고    scopus 로고
    • 2-Azido-5-chlorobenzaldehyde (6c) was prepared by the experimental procedure described by De Mendoza for the preparation of compounds 6b and 6d; see ref. [43]
    • 2-Azido-5-chlorobenzaldehyde (6c) was prepared by the experimental procedure described by De Mendoza for the preparation of compounds 6b and 6d; see ref. [43].


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.