Allen R. Siedle

ortho-Metallation reactions of palladium bis(hexafluoroacetylacetonate)

Abstract ortho -Metallation reactions of palladium bis(hexafluoroacetylacetonate) [Pd(F 6 acac) 2 ] have been studied by 1 H and 19 F NMR. N,N ′-Dimethylbenzylamine produces a fluxional 1 : 1 adduct ( O -F 6 acac)( O 2 -F 6 acac)Pd(amine) which contains a η 1 oxygen-bonded F 6 acac group. The ligands benzyl methyl sulfide and 4,4′-dimethoxythiobenzophenone produce 1 : 1 intermediates of the type (C-F 6 acac)( O 2 -F 6 acac)Pd(ligand) which contain a carbon-bonded F 6 acac group. These adducts spontaneously lose hexafluoroacetylacetone and undergo cyclopalladation at room temperature. Metallation of azobenzene yields (PhNNC 6 H 4 )Pd(F 6 acac) and the doubly ortho -metallated compound (C 6 H 4 NNC 6 H 4 )Pd 2 (F 6 acac) 2 . Similar single metallations occur with benzylideneaniline and acetophenone oxime but thiobenzanilide gave [PhC(S)NPh] 2 Pd and [PhC(S)NPh]Pd(F 6 acac).

Dicarbollide complexes of rhodium and ruthenium

Abstract The 7,8-B9C2H112- ion reacts with (Ph3P)2Rh(CO)Cl to form (B9C2H11)-Rh(Cl)(Ph3P)2. This rhodacarborane reacts with NaBPh4 to produce (B9C2H11-Rh(Ph3P)(Ph4B). The new metallocarboranes [(B9C2H11)Rh(Ph3P)(C6H6)]2 and (B9C2H11)Rh(H)(Ph3P) were obtained from the reaction of B9C2H112- and (Ph3P)3RhCl. The ruthenacarboranes (B9C2H11)Ru(CO)(Ph3P)2 and (B9C2H11-Ru(CO)3 · 0.5C6H6 were prepared from (Ph3P)Ru(CO)2Cl2 and [Ru(CO)3Cl2]2 respectively.

Surface formation of cuprous benzotriazole

Abstract Intense, visible luminescence, attributed to charge transfer excited states, was observed in Cu(I) complexes of benzotriazole but not in the Cu(II) analogues. Microspectrofluorimetry was used to characterize cuprous benzotriazole, a surface phase formed from bulk copper and benzotriazole in dichloromethane.

Organometallic derivatives of trithiones

Complexes of the type LM(CO)5 (M = Cr, Mo) were prepared from (diolefin)M(CO)4 and the 1,3-dithiolene-2-thione ligands, L = C3H2S3, C3H4S3 and C8H6S3. Infrared, 1H and 13C NMR data indicated C4υ symmetry about the metal centre. The reaction of 3-methylbenzo-1,3-dithiolene-2-thione with (C5H5)Co(C8H12) produced a cobalt(III) methylbenzothiete derivative (C7H6S2)-Co(C5H5).

Solvolyis reactions of perfluoro-5-aza-4-nonene, C3F7CFNC4F9

Abstract Hydrolysis of the imine perfluoro-5-aza-4-nonene, C 3 F 7 CFNC 4 F 9 , in ether was studied by several spectroscopic techniques including 17 O NMR. The initial product is C 3 F 7 CONHC 4 F 9 which is converted to (C 3 F 7 CO) 2 NH and then to C 3 F 7 CONH 2 and C 3 F 7 CO 2 H. Solvolysis in liquid ammonia afforded the amidine C 3 F 7 C(NH)NH 2 . Reaction with hydrazine produced 3,5-bis(heptafluoropropyl)-1,2,4-triazole whose crystal structure is reported.

Activation of molecular hydrogen by a nido-metalloborane

Reaction of quaternary ammonium salts of [(B10H12)Ir(CO)(PPh3)2]− in dichloroethane with dideuterium at ambient temperature and pressure leads to reversible HD exchange at two terminal BH sites in the B10H12 ligand. Exchange is thought to occur at the 5–10 boron atoms.

Vaporization of (SN)x and TTF-TCNQ

Abstract The vaporization of (SN)x was studied by electron impact and chemical ionization mass spectrometry. Comparison of the spectra with those of S 4 N 4 suggests that vaporization generates an unstable, acyclic S 4 N 4 which subsequently fragments to a cyclic S 3 N 3 + and SN + ion in the mass spectrometer. Mass spectrometry may be used to analyze (SN)x for S 8 and cage S 4 N 4 . Vaporization of TTF-TCNQ produced the component donor and acceptor molecules.

RESONANCE RAMAN SPECTROELECTROCHEMISTRY. 6. ULTRAVIOLET LASER EXCITATION OF THE TETRACYANOQUINODIMETHANE DIANION

The resonance Raman spectrum has been obtained for the electrogenerated dianion of tetracyanoquinodimethane (TCNQ) upon excitation of its lowest energy electronic transition (A,,, 330 nm) with a frequency doubled, flashlamp- pumped, Rhodamine 640 dye laser. For comparison we report the normal Raman spectrum of solid Li2TCNQmTHF. The elec- tron transfer induced frequency shifts for the second reduction step of TCNQ are measured and interpreted using the *-bond order changes determined from SCF-MO-CI and INDO/S electronic structure calculations as well as the *-bond length changes determined from a MNDO-SCF-MO calculation. Finally, the TCNQZ- Raman data is used to identify the oxidation state of TCNQ in the coordination complex (Co(acacen)(py)2)2TCNQ.

Copper derivatives of tetrathiafulvalene

Oxidation of tetrathiafulvalene with CuCl2.2H2O in ethanol produced the mixed valence metallotetrathia-ethylene (TTF)3(CuCl2)5 containing both TTF+· and TTF2+, which was converted into (TTF)2 CuCl4 on dissolution in hot acetonitrile while the CuCl42– and BF4– salts of TTF2+ were prepared using CuCl2·2H2O and Cu(BF4)2 in acetonitrile; resonance Raman spectroscopy was used to probe the oxidation state of TTF in these copper metallotetrathiafulvalenes, and e.s.r. and magnetic susceptibility data indicate the presence of three-dimensional magnetic interactions in the TTF+ and TTF2+ CuCl42– salts.