Homogeneous catalytic dehydration of sorbitol to isosorbide has been performed with a series of metal tosylates as catalysts. Conversions up to 100 % and selectivities into isosorbide up to 67% were obtained with Bi(OTs)3. The metals were exchanged with acidic sites of sulfonic resins and the resulting materials were evaluated as heterogeneous catalysts. On the contrary to their homogeneous counter
Synthesis and characterization of first row transition metal p-toluenesulfonate complexes and chains
作者:Philip J. Ferko、Jeffrey R. Withers、Hung Nguyen、Charles Allison、Joshua Ema、Tim Ema、Nigam P. Rath、Yuan-Zhu Zhang、Stephen M. Holmes
DOI:10.1016/j.poly.2016.11.047
日期:2017.2
Abstract The preparation, structures, and spectroscopic properties of several molecular complexes and a one dimensional chain are described. A one-dimensional trans-CrII(DMF)2(OTs)2}n (1) chain and mononuclear complexes of trans-[MII(OTs)2(DMF)4] (MII = Fe, 2; Co, 3) and [NiII(DMF)6][OTs]2 (4) stoichiometry are readily obtained from DMF/Et2O solutions containing the parent anhydrous tosylate salts
Synthesis and characterization of one- and two-dimensional octacyanometalate(V) networks: {[trans-MII(DMF)4][cis-MII(DMF)4]2[MV(CN)8]2}n (MII=Mn, Fe, Ni; MV=Mo, W)
作者:Jeffrey R. Withers、Dongfeng Li、Jeremy Triplet、Chad Ruschman、Sean Parkin、Guangbin Wang、Gordon T. Yee、Stephen M. Holmes
DOI:10.1016/j.poly.2007.01.049
日期:2007.6
Treatment of several binary transition metal p-toluenesulfonates [M-II(OTs)(2)] with tri(butyl)ammonium octacyanomolybdate(V) or tungstate(V) in DMF readily affords a series of one- and two-dimensional crystalline octacyanometalate networks of [M-II(DMF)(4)](3)[M-V(CN)(8)](2) (M-V = Mo, W; M-II = Mn, 5, 6; Ni, 7, 8) stoichiometry. Treatment of Fe(OTs)(2) with [HBu3N](3)[W-V(CN)(8)] in DMF affords amorphous precipitates while FeCl3 affords crystalline [Fe-II(DMF)(6)](2)[W-IV(CN)(8)] (9) salts; two-dimensional [Fe-II(DMF)(4)](3)[W-V(CN)(8)](2) (10) lattices are obtained from 9 after standing several months. The structures of 5 and 8 contain [cis-M-II(DMF)(4)(mu-NC)(2)](2+) and [trans-M-II(DMF)(4)(mu-NC)(2)](2+) units that are linked via cyanides to three-connected [M-V(CN)(5)(mu-CN)(3)](3-) centers, forming a one-dimensional chain of M-2(II)(mu-CN)(4)M-2(V)} squares that crystallize in the monoctinic (5, P2(1)/n) and triclinic (8,P (1) over bar) space groups; 6 (P2(1)/n) and 10 (P2(1)/c) crystallize as two-dimensional corrugated sheets containing [cis-M-II(DMF)(4)(mu-NC)(2)](2+), [trans-M-II(DMF)(4)(mu-NC)(2)](2+), and [M-V(CN)(5)(mu-CN)(3)](3-) units in a 4:2:6 ratio. Magnetic measurements indicate that 6 is a ferrimagnet (T-N = 8 K) that exhibits frequency-dependent behavior in chi '' that is qualitatively similar to 1- and 2-D lattices reported by Tang and Holmes, respectively; dc magnetic measurements suggest that 5, 7, and 8 exhibit incipient magnetic ordering while ac measurements show no frequency-dependent behavior in chi ''. Surprisingly, conversion of 5 to 6 in the presence of counterions occurs while heating crystalline samples introduces additional magnetic phases without linkage isomerism; two-dimensional phases containing Mn-II centers appear to be the sole product when wet DMF is used as a reaction solvent. The experimental evidence suggests that coordinated DMF ligands are labile and the M-II(mu-NC)M-V linkages are susceptible to fragmentation. (c) 2007 Elsevier Ltd. All rights reserved.