Theoretical studies on the protonation behavior of tropone and its metal complexes

Fluxional behavior of methyl-substituted tricarbonyl(tropone)iron complexes and their different reactivity

“…Except for the Fe-C(O) distances the differences between the DFT and experimental estimates are less than 2%. Our Fe-C(diene) bond distances of complexes 1 and 3 calculated at B3LYP/6-311+G * level are found to agree within less than 0.01 Å with the corresponding values of Ariafard and Lin calculated at B3LYP level with the basis set of double-zeta quality augmented with a set of polarization functions [14]. The experimentally observed reverse ordering of bond lengths within the diene coordinated to Fe(CO) 3 (the central bond being shorter than the two peripheral bonds) with respect to free tropone is uniformly reproduced by both of the theoretical approaches.…”

“…Calc. for C 14 (7)), 2.42 (dd, 1H, 2 J = 16.9, 3 J 9,10 = 2.3, HC(10)), 1.88 (dd, 1H, 2 J = 16.9, 3 J 9,10 = 2.8, HC(10)), 1.07 (s, 3H, CH 3 C(1)). 13 …”

“…The relative energies of the regioisomers 1a,b and 3a,b (Chart 1) and transition structures connecting these regioisomeric forms were computed by Ariafard and Lin at the DFT level [14]. They found the regioisomeric form 1a and 3a with the methyl-substituted carbon outside the coordination sphere of iron to be more stable by 15.1 kJ mol À1 and 12.1 kJ mol À1 , respectively, than the regioisomeric forms 1b and 3b with the methyl-substituted carbon within the iron coordination sphere.…”

Synthesis and Characterization of 1-Hydroxy-4,5-arene-Fused Tropylium Derivatives

“…NICS(1)/ppm values of 1-hydroxy-4,5-benzotropylium with no substituents [i.e., 4 (R = H)] calculated at the GIAO-B3LYP/6-31+G­(d,p)//ωB97XD/6-31G­(d,p) level were −6.55 and −12.11 for rings A and B, respectively (Figure d). The diatropicity of heptagonal ring A was significantly increased compared to the parent 4,5-benzotropone (−1.06), , as was reported for the corresponding tropone/hydroxytropylium system. , The contribution of 4B was also supported by anisotropy of induced current density (AICD) calculations for 4 (R = H), in which a diatropic ring current originating from a 10π macrocyclic system was observed (Figure b). In contrast, the AICD plot for 3 (R = H) revealed that a strong diatropic ring current was observed only in the fused benzene ring (ring B), while the seven-membered ring possesses a more polyenic character (Figure a).…”

Ni(NHC)]-Catalyzed Cycloaddition of Diynes and Tropone: Apparent Enone Cycloaddition Involving an 8π Insertion

“…Specifically, we studied the catalytic cycles for [Ni­(IPr) 2 ]-catalyzed cycloaddition of nona-2,7-diyne and tropone with DFT calculations . Homocoupling, where two alkynes undergo initial oxidative coupling, and heterocoupling, where an alkyne and the tropone undergo initial oxidative coupling, were both investigated.…”