Jeanette A. Krause Bauer

Novel metallamacrocyclic gold(I) thiolate cluster complex: structure and luminescence of [Au9(μ-dppm)4(μ-p-tc)6](PF6)3

The structure of a novel metallamacrocyclic phosphine gold(I) thiolate cluster, [Au9(mu-dppm)4(mu-p-tc)6](PF6)3, where dppm = bis(diphenylphosphine)methane and p-tc = p-thiocresolate, is reported and shows AuAu attractions of approximately 3.0 A and gold(I) atoms linked to thiolate and phosphine ligands in distorted trigonal and nearly linear geometries.

Reactivity of bis(cyanomethanide) nickel and palladium complexes

The reactivity of the bis(cyanomethanide) nickel and palladium complexes is discussed. The synthetic scheme used to generate these complexes involves the use of a base to generate the anion of acetonitrile, followed by the reaction of this anion with the metal dihalide L 2 NiCl 2 or L 2 PdCl 2 to generate the desired complex L 2 Ni(CH 2 CN) 2 or L 2 Pd(CH 2 CN) 2 . Regardless of the ligand L (PPh 3 , diphos, or bipy), it was found that the complex L 2 Ni(CH 2 CN) 2 is much less stable than the analogous complex L 2 Ni(CH 3 ) 2 . When the cyanomethanide nickel complex is oxidized to induce a reductive–elimination reaction, succinonitrile is generated. Though crystals of a nickel complex could not be obtained, the X-ray structure of the complex (diphos)Pd(CH 2 CN) 2 is reported. Upon oxidation, the palladium complex does not undergo a reductive–elimination reaction.

Use of the aqua complex [ fac -Mn(CO) 3 (dppe)OH 2 ]BF 4 for the preparation of a series of fac -Mn(CO) 3 (dppe)Z and [ fac -Mn(CO) 3 (dppe)Z]BF 4 complexes. X-ray crystal structures of three representative examples

Abstract The aqua ligand in the titled complex (prepared by a simple two-step, high-yield synthesis) is readily replaced by the desired anionic ligand Z−, to give a six-coordinate neutral species fac-Mn(CO)3(dppe)Z. Examples of such complexes where Z O NO2, CN, OMe, OC(O)OMe, and OS(O)2CF3 (OTf) are reported herein. Neutral ligands also replace the aqua ligand to give ionic complexes [fac-Mn(CO)3(dppe)Z]BF4. Examples where Z=2,6-dimethylphenyl (xylyl) isocyanide, acetonitrile, benzonitrile, and acrylonitrile are also reported herein. Crystal structures of fac-Mn(CO)3(dppe)NO3 (2), [fac-Mn(CO)3(dppe)(xylyl-NC)]BF4 (7), and [fac-(CO)3Mn(dppe)(PhCN)]BF4 (9), are reported.

π–π-Stacking and nitro–π-stacking interactions of 1-(4-nitro­phenyl)-4-phenyl-2,4-bis­(phenyl­ethynyl)­buta­diene

The first observed side product, C32H21NO2, in the Sonogashira coupling reaction is reported. The molecular packing shows a high degree of π-stacking interactions in the solid state.

Coupling of isocyanides to alkynes on manganese

Abstract Novel six-membered nitrogen-containing heterocycles bonded to manganese are produced from the reaction of [p-RC6H4CH2C(O)Mn(CO)4(CNC6H4-p-R′)] (1) R′=Me or OMe, R=H or Cl with various alkynes. Trapping of the alkynes by an unsaturated manganese-mono(iminoacyl) group generated in situ leads to formation of: [1-(p-tolyl)-2-(p-chlorobenzyl)-3,4,5,6-tetraphenyl-η5-azacyclohexadienyl]manganese tricarbonyl (2a), [1-(p-methoxy)-2-benzyl-3,4,5,6-tetraphenyl-η5-azacyclohexadienyl]manganese tricarbonyl (2b), [1-(p-tolyl)-2-(p-chlorobenzyl)-3,5-dihydro-4,6-diphenyl-η5-azacyclohexadienyl]manganese tricarbonyl (3a), [1-(p-methoxy)-2-(p-chlorobenzyl)-3,5-dihydro-4,6-diphenyl-η5-azacyclohexadienyl]manganese tricarbonyl (3b), [1-(p-tolyl)-2-(p-chlorobenzyl)-3,5-dimethyl-4,6-bis(carbomethoxy)-η5-azacyclohexadienyl]manganese tricarbonyl (4) and η4-azacyclohexadienyl complexes: [1-(p-tolyl)-2-(p-chlorobenzyl)-3,6-dimethyl-4,5-bis(carbomethoxy)-η4-azacyclohexadienyl]manganese tricarbonyl (5a), [1-(p-tolyl)-2-(p-chlorobenzyl)-3,6-bis(carbomethoxy)-4,5-dimethyl-η4-azacyclohexadienyl]manganese tricarbonyl (5b), [1-(p-tolyl)-2-(p-chlorobenzyl)-4,6-dimethyl-3,5-bis(carbomethoxy)-η4-azacyclohexadienyl]manganese tricarbonyl (5c) and [1-(p-tolyl)-2-(p-chlorobenzyl)-3,4,5,6-tetrakis(carbomethoxy)-η4-azacyclohexadienyl]manganese tricarbonyl (6). All these products result from coupling of one iminoacyl group and two molecules of alkyne. Surprisingly, reaction of 1 with hexafluoro-2-butyne led to formation of an unsaturated five-membered manganacycle [1,1,1,1-tetracarbonyl-2,3-bis(trifluoromethyl)-4-(p-chlorobenzyl)-5-p-tolyl]-5-azamanganacyclopentadiene (7). The structure, reactivity and formation mechanism of these complexes are discussed.

A novel dimanganese complex linked by an unusually strong hydrogen bond. X-ray structure of the hydrogen-bonded complex and ab initio calculations

Abstract In an attempt to prepare the fluoro complex (CO)3(dppe)MnF (3) by treating a CH2Cl2 solution of the aqua complex [(CO)3(dppe)Mn(OH2)]BF4 (1) with NaF(aq), we isolated instead, the dimanganese complex, [(CO)3(dppe)Mn(OH2)⋯FMn(dppe)(CO)3]BF4 (2). The two moieties, 1 and 3, are held together by an unusually strong O–H⋯F hydrogen bond (O⋯F=2.458(3) A, H⋯F=1.52 A) between the aqua ligand on one manganese and the fluoro atom on the other manganese. Using as a simple model the interaction between +Li(H2O) and FLi, the hydrogen bonding distance O–H⋯F was calculated to be; O⋯F=2.443 A. Authentic 3 was prepared in a homogeneous system using CH2Cl2-soluble [Et4N]F.

Conversion of a manganese-carbon-bonded complex to a manganese-oxygen-bonded complex, some reactions of manganese carbonato complexes

Abstract Stirring a solution of the manganese carboxylate, (dppe)(CO) 3 Mn-C(O)OCH 3 , 1 , in dichloromethane saturated with water converts it to the bridging carbonato complex. (dppe)(CO) 3 (dppe), 2 . This multi-step conversion involves the in-situ transformation of a MnC bonded complex to a MnO bonded one. When 2 is stirred with HCl, it is converted quantitatively to the covalent chloride (dppe)(CO) 3 MnCl, 11 , with evolution of carbon dioxide. Similar HCl treatment of the manganese carboxylate 1 gives three compounds: the same covalent chloride, 11 ; the ionic chloride, [(dppe)(CO) 4 Mn] + Cl, 12 , and the hydride, (dppe)(CO) 3 MnH, 5 . Reasonable schemes for these conversions are suggested. Heating the ionic chloride to its melting point converts it to the covalent chloride complex: the same transformation is accomplished by refluxing the ionic chloride in acetonitrile.

Photocyclization of a naphthyl substituted Y-enyne

Y-enyne 1 undergoes electrocyclic ring closure, via a cumulene intermediate 2, to photoproduct 3 upon irradiation at 350 nm in the presence/absence of air. In non-polar solvents, a [1,5] H-shift affords the photoproduct. In MeOX (X=H/D), protonation/deuteration of the central allenic carbon in 2 occurs. The X-ray structure of 3, the photoproduct upon irradiation of 1 in benzene, is reported.

Sequential multiple-photon photochemistry of sterically congested enones

Abstract The photochemistry of sterically hindered enones 1 and 2 is described. A novel photorearrangement occurs in both systems which involves carbonyl attack on the adjacent phenyl ring, expansion of that ring to a cycloheptatriene and subsequent photochemically induced 1,7-phenyl migration.

Synthesis, spectroscopy, and X-ray structures of fac-(CO)3(dppe)MnSC(S)H, fac-(CO)3(dppe)ReSC(S)H, fac-(CO)3(dppp)ReSC(S)H, and fac-(CO)3(dppb)ReSC(S)H

The monodentate dithioformato complexes, fac-(CO)3(dppe)MnSC(S)H (1), fac- (CO)3(dppe)ReSC(S)H (2), fac-(CO)3(dppp)ReSC(S)H (3), and fac-(CO)3 (dppb)ReSC(S)H (4), where dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane, were synthesized from the treatment of the corresponding hydrides, fac-(CO)3 (P-P)MSC(S)H with CS2. Compounds 1–4 crystallize in the monoclinic crystal system: for 1, space group = P21/c, a = 15.3139(3) Å, b = 9.7297(4) Å, c = 19.0991(6) Å, β = 105.928(1)○, V = 2736.5 Å3, Z = 4; for 2, space group = P21/c, a = 15.6395(8) Å, b = 9.8182(5) Å, c = 19.4153(11) Å, β = 106.741(1)○, V = 2854.9(3) Å3, Z = 4; for 3, space group = P21/n, a = 11.3570(10) Å, b = 19.465(2) Å, c = 15.5702(14) Å, β = 104.776(2)○, V = 3328.3(5) Å3, Z = 4; and for 4, space group = C2/c, a = 32.078(2) Å, b = 10.4741(6) Å, c = 19.0608(9) Å, β = 94.315(2)○, V = 6386.1(6) Å3, Z = 8.