Disulfido ligands bonding

Disiloxane, tetramesityl-, 3,206 Disproportionation iridium catalysts, 4,1159 Dissolution nuclear fuels, 6, 927 Distannene, 3,217 Distannoxane, 1,3-dichloro-, 3,207 Distibine, tetraphenyl-, 2,1008 Distibines, 2,1008 Disulfido ligands metal complexes, 2,531-540, 553 bonding, 2, 539 electron transfer, 2, 537 intramolecular redox reactions, 2,537 reactions, 2, 537... 

Disulfido ligands of structure type lb also exist in the interesting compound (NH4 )4 [Mo4 (N0)4 (S2 )5 S3 ] 2H2 O (11), which contains sulfur atoms in five different bonding situations. Four of the five S2 ligands unsymmetrically bridge pairs of Mo atoms (structure type lb). One S ligand is side-on coordinated to a single Mo atom (structure type la). 

High coordination numbers of the metal atom are favored for type I and type III structures by the small coordination angle of bidentate disulfido ligand. High coordination numbers also protect the metal center from nucleophilic attack, an important factor in stabilizing metal-metal bonds. 

The dinuclear rhenium disulfido complex with n,rj -S2 ligands (ReCp )2(/U-S2)2 (Cp =7j -C5Me4Et) (type IIa2 complex in Fig. 2) undergoes an insertion reaction of acetylene and ethylene into the S-S bond according to Scheme 57. 

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