Comparison of the photocatalytic behavior of phosphinated polymer-anchored iron carbonyl species and homogeneous phosphine substituted iron carbonyl species: alkene isomerization and reaction with trialkylsilanes

Reactions of aziridine, thiirane, and oxirane with isocyanide ligands in complexes of palladium(II) and platinum(II): syntheses of neutral five-membered cyclic diamino-, aminothio-, and aminooxycarbene compounds

“…6 The mono(isocyanide) complexes ds-Cl2(L)M(CNR) ( = Pd, Pt; 1-6; Table I) display values of = »( ) µ( -v-(N=C)free7 in the range 78-90 cm™1. For the bis(isocyanide) complexes rá-Cl2M(CNR)2 (M = Pd, Pt; [7][8][9][10][11][12]Table I) the Av shifts are in the range 81-109 cm™1. The positive Av values shown by [1][2][3][4][5][6][7][8][9][10][11][12] indicate that the isocyanide carbon is a potentially reactive electrophilic center8 toward nucleophiles to give carbene complexes.6 However, it has been noticed2 that a positive value of Av (>60 cm™1) appears to be a necessary but not sufficient condition for facilitating reactions of isocyanide ligands with nucleophiles.…”

“…For the bis(isocyanide) complexes rá-Cl2M(CNR)2 (M = Pd, Pt; [7][8][9][10][11][12]Table I) the Av shifts are in the range 81-109 cm™1. The positive Av values shown by [1][2][3][4][5][6][7][8][9][10][11][12] indicate that the isocyanide carbon is a potentially reactive electrophilic center8 toward nucleophiles to give carbene complexes.6 However, it has been noticed2 that a positive value of Av (>60 cm™1) appears to be a necessary but not sufficient condition for facilitating reactions of isocyanide ligands with nucleophiles. In order to test the influence of electronic and steric properties in the reactions of aziridine, thiirane, and oxirane with coordinated RNC ligands, we have examined as typical cases the behavior of aryl isocyanides such as p-MeOC6H4NC and p-MeC6H4NC (higher electron-withdrawing properties of the substituent R) and alkyl isocyanides such as f-BuNC and C6-HnNC (higher sterically demanding properties of the R group).…”

“…All other solvents were of reagent grade purity and used without further purification. *H NMR spectra of the starting isocyanide metal complexes [1][2][3][4][5][6][7][8][9][10][11][12] I) were recorded on a Varían FT-80A spectrometer. The NMR spectra of all the carbene complexes of the type I-III (Table II) were obtained on a Bruker AM-400 spectrometer.…”

“…Starting Complexes. The isocyanide complexes [1][2][3][4][5][6][7][8][9][10][11][12] I) were prepared according to literature procedures, which are outlined in ref 28.…”

Photochemistry of iron and ruthenium carbonyl complexes: evidence for light-induced loss of carbon monoxide and reductive elimination of triethylsilane from cis-mer-HM(SiEt3)(CO)3(PPh3)

“…The photochemistry represented by both equations (3) and (4) The light-induced incorporation of 13 C0 into i and the CO photosubstitut!or -v P(OCH 2 ) 3 CEt raises the issue of whether loss of CO from 1 can play a role in the R 3 SiH exchange chemistry represented by equation (3). The point is that ^0 loss from 1 in the presence of Ph 3 SiH could yield exchange via an oxidative addition/reductive elimination mechanism as indicated in equations (9) and (C)…”