title: Computational comparison of the kinetic stabilities of diamino- and diamidocarbenes in the 1,2-H shift reaction.
abstract: In this study, we performed several DFT, MP2, and BD(T) calculations on the 1,2-H shift reactions of two diaminocarbenes (1, 2) and a diamidocarbene (3) using the Gaussian 09 program. In Gaussian 09, the BD(T) method keyword requests a Brueckner doubles calculation including a perturbative triples contribution. Although N-heterocyclic carbenes (NHC) are typically known for their exceptional σ-donor abilities, recent studies have indicated that π-interactions also play a role in the bonding between NHCs and transition metals or BX3 (X = H, OH, NH2, CH3, CN, NC, F, Cl, and Br) (Nemcsok et al. Organomet 23:3640-3646, 2004, Esrafili. J Mol Model 18:2003-2011, 2012). In order to study the importance of π-interactions between carbenes and transition metals, Hobbs and co-workers (Hobbs et al. New J Chem 34:1295-1308, 2010) focused on the synthesis of NHCs with reduced-energy lowest unoccupied molecular orbitals. By introducing an oxalamide moiety into the heterocyclic backbone, they found the resulting carbene possessed higher electrophilicity than usual NHCs. According to our results, the N,N'-diamidocarbene should be more stable than the diaminocarbenes with respect to the 1,2-H shift reaction.
authors.affiliation: School of Applied Chemistry and Department of Medical Education, Chung Shan Medical University, 402, Taichung, Taiwan. chlai125@csmu.edu.tw
authors.forename: Chin-Hung
authors.initials: CH
authors.lastname: Lai
references.citation: J Chem Theory Comput. 2006 Mar;2(2):364-82
references.pmid: 26626525
references.citation: Phys Rev B Condens Matter. 1992 Sep 15;46(11):6671-6687
references.pmid: 10002368
references.citation: J Mol Model. 2012 May;18(5):2003-11
references.pmid: 21877151
references.citation: Acc Chem Res. 2004 Aug;37(8):534-41
references.pmid: 15311952
references.citation: Nat Chem. 2012 Feb 12;4(4):275-80
references.pmid: 22437711
references.citation: Inorg Chem. 2008 Feb 4;47(3):1145-54
references.pmid: 18166046
references.citation: J Phys Chem A. 2006 Dec 14;110(49):13126-30
references.pmid: 17149824
references.citation: Chem Commun (Camb). 2010 Jun 28;46(24):4288-90
references.pmid: 20480095
references.citation: J Am Chem Soc. 2006 Dec 27;128(51):16514-5
references.pmid: 17177396
references.citation: Inorg Chem. 2009 Jun 15;48(12):5361-9
references.pmid: 19400577
references.citation: Phys Rev B Condens Matter. 1988 Jan 15;37(2):785-789
references.pmid: 9944570
references.citation: Acc Chem Res. 2008 Feb;41(2):157-67
references.pmid: 18186612
references.citation: J Am Chem Soc. 2012 Apr 11;134(14):6116-9
references.pmid: 22463070