1425924-84-0Relevant articles and documents
C-C bond formation and related reactions at the CNC backbone in (smif)FeX (smif = 1,3-di-(2-pyridyl)-2-azaallyl): Dimerizations, 3 + 2 cyclization, and nucleophilic attack; Transfer hydrogenations and alkyne trimerization (X = N(TMS)2, dpma = (Di-(2-pyridyl-methyl)-amide))
Frazier, Brenda A.,Williams, Valerie A.,Wolczanski, Peter T.,Bart, Suzanne C.,Meyer, Karsten,Cundari, Thomas R.,Lobkovsky, Emil B.
, p. 3295 - 3312 (2013)
Molecular orbital analysis depicts the CNCnb backbone of the smif (1,3-di-(2-pyridyl)-2-azaallyl) ligand as having singlet diradical and/or ionic character where electrophilic or nucleophilic attack is plausible. Reversible dimerization of (smif)Fe{N(SiMe3)2} (1) to [{(Me3Si)2N}Fe]2(μ-κ3, κ3-N,py2-smif,smif) (2) may be construed as diradical coupling. A proton transfer within the backbone-methylated, and o-pyridine-methylated smif of putative (bMe2 oMe2smif)FeN(SiMe3)2 (8) provides a route to [{(Me3Si)2N}Fe]2(μ- κ4,κ4-N,py2,C-(bMe, bCH2,oMe2(smif)H))2 (9). A 3 + 2 cyclization of ditolyl-acetylene occurs with 1, leading to the dimer [{2,5-di(pyridin-2-yl)-3,4-di-(p-tolyl-2,5-dihydropyrrol-1-ide)}FeN(SiMe 3)2]2 (11), and the collateral discovery of alkyne cyclotrimerization led to a brief study that identified Fe(N(SiMe 3)2(THF) as an effective catalyst. Nucleophilic attack by (smif)2Fe (13) on tBuNCO and (2,6-iPr 2C6H3)NCO afforded (RNHCO-smif)2Fe (14a, R = tBu; 14b, 2,6-iPrC6H3). Calculations suggested that (dpma)2Fe (15) would favorably lose dihydrogen to afford (smif)2Fe (13). H2-transfer to alkynes, olefins, imines, PhNNPh, and ketones was explored, but only stoichiometric reactions were affected. Some physical properties of the compounds were examined, and X-ray structural studies on several dinuclear species were conducted.
