Dioxomolybdenum(VI) complexes including MoO2(dipic)(HMPA) 2a and MoO2(dedtc)2 2b (dipic = 2,6-pyridinedicarboxylate; HMPA = hexamethylphosphoramide; dedtc = N,N-diethyl dithiocarbamate) catalyse the allylic amination of alkenes by phenyl hydroxylamine; the reactions are characterized by a high degree of regioselectivity resulting from double bond migration.

Chapter 5.8.2.4.5. π-Allyl Metal Complexes by Oligomerization of Conjugated Dienes S. S. Wreford, S. S. WrefordSearch for more papers by this authorR. Pankayatselvan, R. PankayatselvanSearch for more papers by this authorK. Nicholas, K. NicholasSearch for more papers by this author S. S. Wreford, S. S. WrefordSearch for more papers by this authorR. Pankayatselvan, R. PankayatselvanSearch for more papers by this authorK. Nicholas, K. NicholasSearch for more papers by this author Book Editor(s):J. J. Zuckerman, J. J. ZuckermanSearch for more papers by this authorA. P. Hagen, A. P. HagenSearch for more papers by this author First published: 01 January 1991 https://doi.org/10.1002/9780470145272.ch22Book Series:Inorganic Reactions and Methods AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Inorganic Reactions and Methods: Formation of Bonds to Elements of Group IVB (C, Si, Ge, Sn, Pb) (Part 4), Volume 12 RelatedInformation

The addition of several nucleophiles to a series of (η4-diene)Co(CO)3BF4 complexes has been examined in order to probe the effect of diene substituents and the nature of the nucleophile on the regioselectivity of attack on the coordinated diene. The dienes include 1-substituted dienes: trans-1,3-pentadiene (piperylene), 1-trimethylsilyl-2,4-pentadiene; 2-substituted dienes: 2-methyl- (isoprene), 2-ethyl-, 2-phenyl-, 2-para-fluorophenyl-, and 2-trimethylsilylmethyl-1,3-butadiene; and the disubstituted diene 2-methyl-1,3-pentadiene. The set of nucleophiles includes NaBH3CN, C6H5MgBr, P(CH3)3, C5H5N (pyridine), and N(CH2CH3)3. The reactions occur generally with a high degree of regioselectivity according to the following trends: (1) addition of nucleophiles to most complexes occurs preferentially or exclusively at C(4) (terminal diene carbon remote from the substituent); (2) noteworthy exceptions include the isoprene complex, in which modest C(1) addition selectivity is observed with Nu = NaBH3CN, C6H5MgBr, P(CH3)3 and the dimethyl derivative (for Nu = pyridine); and (3) the selectivity for C(4) attack is nucleophile dependent, decreasing in the order N(CH2CH3)3 > pyridine > P(CH3)3 > C6H5MgBr > NaBH3CN. A combination of steric and frontier molecular orbital effects is proposed to explain the observed regioselectivity.