A number of isomeric N-benzylbenzalimine palladium(II) complexes of the type [PdX(o-C6H4 · C(CH)3)N·CH2Ph]2 (with CN endo to the palladocycle) and [PdX(o-C6H4 · CH2NC(CH3Ph]2 (with CN exo to the palladocycle), have been prepared and charcterised by 1H and 13C NMR methods. The crystal structures of two analogous monomeric acac complexes, synthesized independently by oxidative addition of o-BrC6H4CH2NCH · Ph to Ph to Pd(dibenzylideneacetone)2 have also been determined. These are [Pd(acac)(o-C6H4 · CHN · CH2Ph)] (15a) and [Pd(acac)(o-C6H4 · CH2NCHPh)] (20a). Crystals of 15a are monoclinic, space group P21/a with Z = 4 in a cell of dimensions a 10.286(2), b 11.902(3), c 13.895(5) Å, β 93.52(2)° while 20a is monoclinic, space group P21/c with Z = 8 and a 10.353(3), b 20.600(5), c 16.545(7) Å, β 92.14(3)°. The structures 15a and 20a were refined to residuals R = 0.041 and 0.055 for 1661 and 2525 observed reflections respectively.

Chemischer InformationsdienstVolume 17, Issue 28 Heterocyclic Compounds ChemInform Abstract: Palladium-Assisted Organic Reactions. Part 8. Simple Synthesis of 2,3-Disubstituted Phthalimidines. N. BARR, N. BARRSearch for more papers by this authorJ. P. BARTLEY, J. P. BARTLEYSearch for more papers by this authorP. W. CLARK, P. W. CLARKSearch for more papers by this authorP. DUNSTAN, P. DUNSTANSearch for more papers by this authorS. F. DYKE, S. F. DYKESearch for more papers by this author N. BARR, N. BARRSearch for more papers by this authorJ. P. BARTLEY, J. P. BARTLEYSearch for more papers by this authorP. W. CLARK, P. W. CLARKSearch for more papers by this authorP. DUNSTAN, P. DUNSTANSearch for more papers by this authorS. F. DYKE, S. F. DYKESearch for more papers by this author First published: July 15, 1986 https://doi.org/10.1002/chin.198628221Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume17, Issue28July 15, 1986 RelatedInformation

Electron-poor alkenes such as alkyl acrylates have been found to insert into the aromatic carbon—palladium bond in orthobromobenzamides under the conditions of the Heck reaction. For primary and secondary benzamides a further palladium-catalysed reaction occurs to yield 3-substituted, or 2,3-disubstituted phthalimidines.

Isolated SnH stretching frequencies have been obtained from i.r. spectra of SnHD3, MeSnHD2, EtSnHD2, Me2SnHD, Et2SnHD, Me3SnH and Et3SnH. 2νisSnH frequencies are also reported for Me2SnHD and Me3SnH. Two bands separated by 3.6 cm−1 in the case of EtSnHD2 represent the differing β effects of the methyl group. A close comparison of the SnH data with earlier GeH ones indicates that the conformers predominating in both Et2SnH2 and Et3SnH have all methyl groups gauche to the SnH bonds, in contrast to the situation in analogous GeH compounds.

A new, improved method is described for the preparation of cyclopalladated benzalimines; it consists of reacting the ortho-bromobenzalimine with bis(dibenzylideneacetone) palladium(0). A number of substituted o-bromobenzalimines has been studied; the bridged bromide dimers and the corresponding bromo (N-substituted benzalimine-6,C,N)triphenylphosphinepalladium(II) complexes have been fully characterised and 1H and 13C NMR spectral data recorded. In the cases of the N-phenylbenzalimines studied, bis(triphenylphosphine) complexes were also isolated and characterised.

AbstractDie Palladium‐Komplexe (III) reagieren mit Acylchloriden (IV) bevorzugt unter ortho‐Acylierung zu den Produkten (VII).

Cyclopalladated complexes of primary, secondary and tertiary bezylamines and of benzalimines have been prepared by the oxidative addition of the corresponding ortho-bromobenzylamine and ortho-halobenzalimine to bid(dibenzylideneacetone)palladium(0). The complexes have been characterised fully as the monomeric triphenylphosphine derivatives.

Complexes of Group VI metal carbonyls with the ligand bis(di-o-tolyl)phosphinomethane have been prepared and characterised by NMR spectroscopy. The crystal structure of Cr(CO)2(BDToM) has been determined by conventional X-ray diffraction techniques. The orange tabular crystals are monoclinic, space group Cc, a 24.197(1), b 8.162(1), c 16.736(1) Å, β 124.14(1)°, V 2735.8 Å3, Z = 4. Refinement by full-matrix least-squares methods employed anisotropic thermal parameters for the heavier atoms and the coordinated o-tolyl group. One carbonyl ligand was positioned from a ‘difference’ map. The final residual, R, is 0.078 for 1673 observed reflections.

The reactions between two di-μ-chloro-bis(N,N-dialkylbenzylamine-2-C,N)dipalladium(II) complexes, and two [ethyl di-μ-chloro-bis(N-methyl-N-benzyl-2-C,N)-glycinate]dipalladium(II) complexes with a variety of acyl halides have been studied. Regiospecific ortho-acylation occurs in good to high yields in most examples. The intermediate complexes of the type [LPdCl2]2 were characterised in two cases (L = ortho-acylbenzylamine derivative). No insertion reactions were observed with (C6H5)3C·COCl or with (CH3)3C·COCl. The cyclisations of two of the ortho-acylbenzylglycinates to isoquinoline derivatives are described, to illustrate the utility of these acylation reactions in synthetic nitrogen heterocyclic chemistry.

The starting material chlorodi(o-tolyl)phosphine has been prepared by the reaction of phosphorus trichloride and the Grignard of o-chlorotoluene. The intermediate lithium di(o-tolyl)phosphide was obtained by the direct reaction of lithium metal and chlorodi(o-tolyl)phosphine in tetrahydrofuran. Lithium di(o-tolyl)phosphide reacted smoothly with ω,ω'-dihaloalkanes, X(CH2)nX (n  1-4, 6, 8, X  Cl or Br) to form the tertiary diphosphines (o-tolyl)2P-(CH2)nP(o-tolyl)2. Chlorodi(o-tolyl)phosphine and the diphosphines (o-tolyl)2P-(CH2)nP(o-tolyl)2 (n  1-4, 6, 8) were characterised by elemental analyses and 1H, 31P and 13C NMR spectral analyses.

The complexes RhCl (CO) {PPh2[(CH2)nCHCH2]}2 and RhCl (CO) add hydrogen in methanol solution saturating the olefin and forming RhCl (C0) {PPh2 [(CH2)n+1CH3]}2, n = 0–3. The reaction does not proceed in non-protic solvents. Carbon monoxide inhibits the reaction, whereas excess ligand (for n = 2) becomes catalytically saturated. The rate of the reaction depends largely on steric factors and follows the order RhCl (CO) [PPh2 (CH2CH2CHCH2)]2 > RhCl (CO) [PPh2(CH2CH2CH=CH2CH3)]2 ~ RhCl (CO) [PPh2 (CH2CH2CH2CHCH2)]2 > RhCl (CO) [PPh2(CH2CHCH2)]2 > RhCl (CO) [PPh2(CHCH2)]2. Deuteration experiments show that scrambling does occur and a mechanism for the hydrogenation is proposed. Isomerisation for n = 3 occurs at higher temperatures giving the cis-olefinphosphine complex RhCl (CO)

Studies of the 13C N.M.R. spectra of the series RhX[P(Ch2CH2CHCH2)3] and RhX[P(CH2CH2CH2CHCH2)3] where x  Cl or Br have revealed that (a) the J(103Rh-13C) (olefin) for the complexes studied is only 12 − 13 that found for square-planar complexes, and (b) the fluxional character in the olefinic carbons observed for the compounds RhX[P(CH2CH2CHCH2)3] is related to the partial rotation of the olefin about the rhodium-olefin bond.

AbstractDas Bibenzyl (I) wird von dem Rhodiumkomplex (II) sowie von anderen Rhodiumkomplexen unter Bildung von (IIIa) dehydriert; (IIIb) entsteht entsprechend.

Rhodium(I) and iridium(I) complexes effect the dehyddrogenation of the alkane chain in the ligand 1,6-bis(diphenylphosphino)hexane forming the metal olefin complexes (BDPH)MCl where BDPH = 1,6-bis(diphenylphosphino)-trans-hex-3-ene and M = Rh or Ir.

2,2′-Bis(o-diphenylphosphino)bibenzyl, o-Ph2PC6H4CH2CH2C6H4PPh2-o (bdpbz), is dehydrogenated by various rhodium complexes to give the planar rhodium(I) complex , from which the ligand, 2,2′-bis(o-diphenylphosphino)-trans-stilbene (bdpps) can be displaced by treatment with sodium cyanide. The stilbene forms stable chelate olefin complexes with planar rhodium(I) and iridium(I) and with octahedral iridium(III). On reaction with halide complexes of nickel(II), palladium(II) or platinum(II), the stilbene ligands (R  Ph or o-CH3C6H4) lose a vinyl proton in the form of hydrogen chloride to give chelate, planar σ-vinyls of general formula MX(o-R2PC6H4CCHC6H4PR2-o) (M  Ni, Pd, Pt; X  Cl, Br, I) of high thermal stability; analogous methyl derivatives Pt(CH3)(o-R2PC6H4CCHC6H4PR2-o) are obtained from Pt(CH3)2(COD) (COD  1,5-cyclooctadiene) and the stilbene ligands. The bibenzyl also forms chelate σ-benzyls MX(o-Ph2PC6H4CHCH2C6H4PPh2-o) (M  Pd, Pt; X  Cl, Br, I). The 1H NMR spectra of the o-tolyl methyl groups in the compounds MX(o-R2PC6H4CCHC6H4PR2-o) (M  Ni, Pd, Pt; R  o-CH3C6H4) vary with temperature, probably as a consequence of interconversion of enantiomers arising from restricted rotation about the MP and MC bonds. Possible mechanisms for the dehydrogenation reactions are briefly discussed.

AbstractDarstellung und Reaktionen der Rhodium‐Komplexe (III) und (VI), sowie ihrer Iridium‐Analoga (IX) werden beschrieben.

But-3-enyldiphenylphosphine (mbp) and diphenylpent-4-enylphosphine (mpp) react with Rh2Cl2(C2H4)4 (molar ratio 21 to form the four coordinate dimeric complexes Rh2Cl2(mbp)2 and Rh2Cl2(mpp)2 respectively, while but-3-enyldiphenylphosphine reacts with Rh2Cl2(C2H4)4 (molar ratio 41) to form RhCl(mbp)2, a five coordinate complex in the solid state. The dimers further react with sodium tetraphenylborate to give the π-bonded tetraphenylborate complexes Rh[mbp][C6H5)4B] and Rh[i-mpp][(C6H5)4B] where i-mpp = (C6H5)2P(CH2CH2CHCHCH3). RhCl(CO)(mbp)2 reacts with sodium tetraphenylborate to form the five coordinate cationic complex [Rh(CO)(mbp)2][(C6H5)4B]. Both RhCl(CO)(mbp)2 and RhCl(mbp)2 react with hydrogen in methanol saturating the olefin to form RhCl[CO][(C6H5)2P(C4H9)]2 and Rh2Cl2[(C6H5)2P(C4H9)]2 respectively.

The rhodium(I) and iridium(I) complexes, RhX(tbp), RhX(tpp), X = Cl, Br or I, and IrCl(tbp) and IrCl(tpp) where tbp = P(CH2CH2CH=CH2)3 and tpp = P(CH2CH2CH2CHCH2)3 have been prepared. These compounds, except for RhI(tbp), all exhibit the same “umbrella” type five coordinate structure in the solid state, in which all three olefins are bonded to the metal. At −60° in solution, RhI(tbp) adopts the same five coordinate stereochemistry. Due to restricted rotation, the methylene protons in RhCl(tbp) become inequivalent at low temperature. RhCl(tbp) forms 11 adducts with carbon monoxide and triphenylphosphine. Infrared, Raman and PMR studies conclude that the metalolefin bond is stronger for the iridium complexes compared to the corresponding rhodium complexes.