Papers of General Interest

The ability of [Fe2(CO)g(y-SMe)2I to act as a catalyst in substitution reactions of metal carbonyls has been noted. 

Elimination of CO following the electrode reduction to [M(CO) (bipy)] radical anions is the rate-determining step.  

The [Cp2Fe) oxidation of lCpFe(CO)2)2 Co lCOg and iCpNilCO)] the presence of FFh results in the formation of mononuclear iCpFe(C0)2(PPhg)], trans-[Co (CO) (PPh ) and (CpNi (PPh ) 2],  

H R = Pr, R = Me) and [HFe(CO) ] follow a different course producing the metal-metal bonded complexes 

Whereas [RU2(CO) (RN=CHCH=NR)] (R = Pr, Cy, or CyCH2) reacts with H2 to give [H2RU2(CO) (RN=CHCH=NR)] oxidative addition products containing 6-electron donor DAB, when R = neo-pentyl the product is the novel complex (5) with a Ru linear chain and 8-electron donor DAB ligands. 

Carbene Complexes.— Protonation of the chelated iron-carbene complex (59) in the presence of ethylene yields (60), the first example of a metal-carbene-olefin complex of the type postulated as intermediates in olefin metathesis reactions. Hydride abstraction from (61) affords (62). The new carbene complexes (63), (64), and (65) have been prepared by treatment of [Fe(jj-C5H5)(SnPh3)-(CO)(CS)l, [Fe( -C6H6) C(S)OPh (CO)3], and [Fe( -CS3) P(OMe)3 (CO)3] with ethylenediamine, methylfluorosulphonate (followed by methanol and PF e ions), 

A mechanism involving enantioface selective olefin attack upon transient chiral cobalt carbene complexes formed from prochiral diazoalkanes has been proposed to account for the high degree of enantioselectivity observed in cobalt-(ii) catalysed olefin cyclopropanation using chiral diazoalkanes.  

Alkoxycarbene complexes of nickel(n), /mnj -[Ni(C6Cl5) C(OR )Me (PMe2-Ph)2][C104] have been synthesized by treatment of the acetylides /ra j [Ni-(C=CR)(C6Cl5)(PMe2Ph)2] with selected alcohols in the presence of perchloric acid.  

Hiraki, M. Onishi, K. Sewaki, and K. Sugino, Bull. Chem. Soc. Japan, 1978, 51, 2548. 

This Section considers ligands that have been reacted with metal carbonyls from more than one group of the Periodic Table. 

Ccxnplexes containing DAB ligands (RN=CHCH=NR R=alkyl) continue to be explored. Reactions between Fe2(CO) and [Fe(CO) (DAB)] lead to [Fe2(CO)g(DAB)] products containing six-eiectron donor DAB. 

Na[MeGa(pz)g] gives the metal-metal single bonded complex 

2) have also been Isolated. Similar reactions using [Re(C0) Cl]2 have led to the chelate complexes Re(CO)jL[Me2Ga pz)2]) and Re(CO) 2l lMe2Ga(pz) (OH) ] (L = CO, or pyrazole). Some 

5-dimethylpyrazolyl analogues have been characterised. The novel anions Me2Ga(pz)[OCH2(C H N)] and 

Montasti, E. Pelizzetti, and G. Saini, J. Inorg. Nuclear Chem., 1976,38, 785. 

The angular overlap model has been used to determine the relative stability of the systems, cis- and rrans-MA2B4, isomers of MA3B3, axially and equatorially substituted square-pyramidal and trigonal-bipyramidal MAB4 and square-planar MA2B2- The most stable isomer was predicted in each case, based on d-orbital stability.  

The following relevant reviews have been published. 

Metal Carbonyls some new observations in an old field (F. A. Cotton, Progr. Inorg. Chem., 1976, 21, 1). 

High nuclearity metal carbonyl clusters (P. Chini, G. Longoni, and V. G. Albano, Adv. Organometallic 

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Photochemical Urban Atmospheric Pollution.—Many of the reactions discussed in the headings above are of importance in an understanding of photochemically induced atmospheric pollution in urban situations, and are also important in stratospheric aeronomy. The remote sensing of airborne pollutants has been covered in Section 11, but we present here briefly the subject of some papers of general interest to atmospheric pollution. 

Jeffrey and Sundaralingam have provided a further bibliography of crystal structures of carbohydrates, nucleosides, and nucleotides, and a paper of general interest relates to a survey of 161 published structures of pyranose derivatives. This led to the establishment of average orthogonal co-ordinates. Specific crystal structures have been reported as follows, neutron diffraction studies being identified by the letters n.d. ... 

Attention is first called to some papers of general interest. A new collection of Q and e values, particularly useful for copolymerization studies, will also be useful in other connections, e.g., initiation and transfer. The hot radical theory has been applied again to account for kinetic abnormalities in polymerizations, but another explanation has been based upon changes in the activity coefficients of monomers. Some new general kinetic relationships have been derived with emphasis on integral treatments. ... 

Other papers of general interest deal with several new metal carbonyl cluster complexes molecular approaches to heterogeneous catalysis and a new perspective for the synthesis of metal-carbonyl clusters the reactions of carbonyl clusters with strained ring thioethers and the use of tri(m-sulphonatophenyl)phosphine salts as water solubilizing agents for carbonyls and carbonyl hydrides 2. 

A paper of general interest is a review which concerns the chemistry of boron analogues of biomolecules (345 references). Also of general appeal are the first examples of the use of two-dimensional B- correlation NMR spectroscopy. ... 

The mechanistic interpretation of volume of activation and reaction volume data according to a volume profile analysis cannot be treated in this compilation. However, we would like to direct the readers attention to some interesting papers of general interest to this topic in the following references a method to estimate the intrinsic term in activation and reaction volumes/ the ionic-strength dependence of volumes of activation/ the correction for the compressibility of the solvent/ the role of nonlabile ligands in the interpretation of volumes of activation/ and the theoretical prediction of partial molar volumes and volumes of activation. 

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