title: Intramolecular oxyallyl-carbonyl (3 + 2) cycloadditions.
abstract: Cycloadditions involving oxyallyl intermediates typically require an electron-rich diene or alkene, but we have discovered the first examples of the cycloaddition of heteroatom-stabilized oxyallyls onto carbonyl groups. An oxazolidinone-substituted oxyallyl undergoes chemoselective (3 + 2) cycloaddition onto the carbonyl group of a tethered dienone in preference to formation of the expected (4 + 3) cycloadduct. Density functional theory calculations indicated that the (3 + 2) cycloaddition takes place through a concerted, highly asynchronous mechanism. The transition state features simultaneous interactions of the oxyallyl LUMO with the carbonyl π and lone-pair orbitals, making this reaction "hemipseudopericyclic" (halfway between purely pericyclic and purely pseudopericyclic). Further (3 + 2) cycloadditions involving tethered phenyl ketones and a tethered enone were predicted theoretically and verified experimentally.
authors.affiliation: School of Chemistry, The University of Melbourne, and Australian Research Council Centre of Excellence for Free Radical Chemistry and Biotechnology, VIC 3010, Australia. e.krenske@uq.edu.au
authors.forename: Elizabeth H
authors.initials: EH
authors.lastname: Krenske
authors.forename: Shuzhong
authors.initials: S
authors.lastname: He
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Du
authors.forename: K N
authors.initials: KN
authors.lastname: Houk
authors.forename: Richard P
authors.initials: RP
authors.lastname: Hsung
mesh_terms: D000498:Allyl Compounds / Q000737:chemistry*; D003500:Cyclization; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D011789:Quantum Theory
chemical_list: D000498:Allyl Compounds; D007659:Ketones
references.citation: J Org Chem. 2013 Mar 1;78(5):1753-9
references.pmid: 22849303
references.citation: Chemistry. 2005 Oct 7;11(20):5966-74
references.pmid: 16052635
references.citation: Phys Rev B Condens Matter. 1988 Jan 15;37(2):785-789
references.pmid: 9944570
references.citation: Angew Chem Int Ed Engl. 2012 Oct 8;51(41):10390-3
references.pmid: 22969063
references.citation: Org Lett. 2007 Mar 29;9(7):1275-8
references.pmid: 17335226
references.citation: Chemistry. 2011 Mar 28;17(14):3812-22
references.pmid: 21384451
references.citation: Angew Chem Int Ed Engl. 2012 Nov 26;51(48):12120-3
references.pmid: 23097373
references.citation: J Am Chem Soc. 2011 May 25;133(20):7664-7
references.pmid: 21513358
references.citation: Angew Chem Int Ed Engl. 2004 Apr 2;43(15):1934-49
references.pmid: 15065270
references.citation: J Am Chem Soc. 2002 May 8;124(18):5231-41
references.pmid: 11982388
references.citation: J Am Chem Soc. 2001 Jul 25;123(29):7174-5
references.pmid: 11459504
references.citation: Acc Chem Res. 2002 Oct;35(10):867-77
references.pmid: 12379139
references.citation: J Phys Chem B. 2009 May 7;113(18):6378-96
references.pmid: 19366259
references.citation: J Am Chem Soc. 2003 Oct 22;125(42):12694-5
references.pmid: 14558802
references.citation: Chem Commun (Camb). 2011 Mar 28;47(12):3416-7
references.pmid: 21311803
references.citation: Chem Sci. 2010 Sep 1;1(3):387-392
references.pmid: 21572919
references.citation: Org Lett. 2000 Apr 6;2(7):883-6
references.pmid: 10768177
references.citation: J Phys Chem A. 2005 Jun 30;109(25):5636-44
references.pmid: 16833896
references.citation: J Org Chem. 2001 Aug 24;66(17):5832-9
references.pmid: 11511259
references.citation: J Am Chem Soc. 2011 Sep 14;133(36):14443-51
references.pmid: 21851070
references.citation: Org Lett. 2010 Dec 3;12(23):5506-9
references.pmid: 21049917
references.citation: Chemistry. 2006 Apr 24;12(13):3438-47
references.pmid: 16402402
references.citation: Chem Commun (Camb). 2010 Dec 21;46(47):8904-22
references.pmid: 21063614
references.citation: J Am Chem Soc. 2009 Apr 8;131(13):4556-7
references.pmid: 19281161
references.citation: Chem Commun (Camb). 2010 Dec 21;46(47):8886-903
references.pmid: 21057692
references.citation: Angew Chem Int Ed Engl. 2004 Feb 1;43(5):615-8
references.pmid: 14743419
references.citation: Acc Chem Res. 2008 Feb;41(2):157-67
references.pmid: 18186612
references.citation: J Am Chem Soc. 2003 Feb 26;125(8):2058-9
references.pmid: 12590528
references.citation: J Am Chem Soc. 2005 Jan 12;127(1):50-1
references.pmid: 15631443