89286-44-2Relevant academic research and scientific papers
RHENIUM CARBONYL COMPLEXES. SYNTHESIS AND CHARACTERISATION OF NN'-DIARYLAMIDINES, R'NHC(R)NR' (R=H, Me, or Ph, R'=Ph or C6H4Me-p), AND RELATED CARBAMOYL DERIVATIVES
Clark, J. Andrew,Kilner, Melvyn
, p. 389 - 398 (2007/10/02)
NN'-Diarylacetamidines R'NHC(Me)NR', NN'-diarylbenzamidines R'NHC(Ph)NR', and NN'-diarylformamidines R'NHC(H)NR' (R'=Ph or C6H4Me-p) react thermally or photolytically with and/or 2> (X= Cl or Br) to afford air-stable, white complexes, X>, containing monodentate amidine ligands.The corresponding lithioamidines (R= Me or Ph) gave white carbamoyl complexes >, which are converted thermally to NN'-bidentate > and ortho-metallated > (R''=H or Me).The latter complexes are also formed by further reaction of the carbamoyl complexes with the corresponding amidine.The carbamoyl complexes react with PPh3 to form >.Lithioamidines in excess react with (X= Cl or Br) complexes to give adducts formulated as Li(1+)2>(1-).The new complexes are characterised, and structural data obtained by i.r. and n.m.r. spectroscopy.
Amidino-complexes of Rhenium. Bidentate NN'- and ortho-Metallated Derivatives
Clark, J. Andrew,Kilner, Melvyn
, p. 2613 - 2624 (2007/10/02)
> complexes (I; R=Me or Ph; R'=Ph or C6H4Me-p), containing delocalised bidentate NN'-chelated amidino-groups, have been prepared by reactions of (i) 2> (X=Cl or Br) with R'N(Li)C(R)NR', (ii) X> with LiBun, (iii) with R'NHC(R)NR', and (iv) by decarbonylation of > complexes.Triphenylphosphine displaces CO from (I) to form > (II), which are more conveniently prepared by the reactions of (L'=PPh3 or AsPh3) with amidines in refluxing toluene.This reaction stops at the intermediate compound Br> when a NNN'-trisubstituted amidine is used.Related complexes Br> are formed when (II) are treated with hydrobromic acid. (X=Cl or Br) and 2> react with amidines to form o-metallated > (R=H, R'=Ph; R''=H; R=Me or Ph, R'=C6H4Me-p, R''=Me; R=Me or Ph, R'=Ph, R''=H) complexes which contain a six-membered o-metallated ring.Benzamidines (R=Ph) produce in addition an isomeric complex in which o-metallation of the R substituent occurs to give complexes having five-membered o-metallated rings.Intermediate 2X> complexes were isolated for R'=C6H4Me-p, R=Me, and X=Cl or Br.A 1,3-proton-shift mechanism for the o-metallation reaction is eliminated by the formation of the complex > (R'=C6H4Me-p) from R'N(Me)C(Me)NR'.Reaction schemes are suggested for the course of the reactions, and structures for the new complexes are proposed on the basis of spectroscopic data.
