Mononuclear termination

Spontaneous transfer reactions in conjugated diene polymerisation systems are more complex than those in monoalkene polymerisation systems. Two types of chain termination reaction can occur in principle in polymerisation systems containing conjugated diene. The first type, mononuclear termination, consists in a hydrogen abstraction from the growing chain with the formation of an Mt H bond [scheme (7)] which reforms an Mt [ /3-(All)] bond on reaction with the monomer ... 

A mononuclear, terminal Cu -hydroperoxide complex has been obtained by Masuda and colleagues through reaction at room temperature of the cupric complex of the tripodal ligand bis(6-pivalamide-2-pyridylmethyl)-(2-pyridylmethyl)amine with excess hydrogen peroxide... 

Figure 15 A mononuclear, terminal Cu -hydroperoxide complex, obtained by Masuda and colleagues. ...

Titanium imido complexes supported by amidinate ligands form an interesting and well-investigated class of early transition metal amidinato complexes. Metathetical reactions between the readily accessible titanium imide precursors Ti( = NR)Cl2(py)3 with lithium amidinates according to Scheme 84 afforded either terminal or bridging imido complexes depending on the steiic bulk of the amidinate anion. In solution, the mononuclear bis(pyridine) adducts exist in temperature-dependent, dynamic equilibrium with their mono(pyiidine) homologs and free pyridine. 

Proudfoot AE, Buser R, Borlat F et al (1999) Amino-terminally modified RANTES analogues demonstrate differential effects on RANTES receptors. J Biol Chem 274 32478-32485 Qin AP, Zhang HE, Qin ZH (2008) Mechanisms of lysosomal proteases participating in cerebral ischemia-induced neuronal death. Neurosci Bull 24 117-123 Richter R, Bistrian R, Escher S et al (2005) Quantum proteolytic activation of chemokine CCL15 by neutrophil granulocytes modulates mononuclear cell adhesiveness. J Immunol 175 1599-1608... 

The cyanato ligand generally tends to bind through its N atom to Ni11 and acts as an N-bound terminal ligand in mononuclear complexes. Complexes of the type [Ni(NCO)2L4] (L = py, H20)... 

Figure 20 A mononuclear tetrahedral complex with a chelating dppf02 and two terminal chlorides.

To provide a model for nitrite reductases72 Karlin and co-workers characterized a nitrite-bound complex (226) (r = 0.05)214 In an endeavor to model nitrite reductase activity, Tanaka and co-workers prepared a few mononuclear complexes (227) (r = 0.74)215 (228) (r = 0.82),216 (229) (r = 0.97),217 (230) (r = 0.16),217 (231) (r = 0.07),217 and (232) (r = 0.43 and r = 0.53)217 and studied the electrochemical reduction of N02A As a part of their activity on modeling heme-copper terminal oxidases, Holm and co-workers prepared complex (233) (r = 0.96).218 Using a sterically hindered tris(pyridylmethyl)amine, Canary et al. prepared a complex (234) (r=1.00), studied its redox behavior, and discussed various factors that may contribute to the difference (higher potential for the new complex) in the redox potential of a Cu Cu1 couple between substituted and unsubstituted ligands.2 9... 

Herrmann has reported the reaction of the mercury diazo compound Hg(CN2C02Et)2 with Mn(CO)sBr to afford the biscarbyne-bridged dimer 90 (128). The intermediacy of a terminal mononuclear carbyne complex 89 is strongly implicated here ... 

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