1.4.7- Triazacyclononane complexes

SCHEME 87. Enantioselective olefin epoxidation using chiral Mn/l,4,7-triazacyclononane complexes... 

For lead with its relatively large radius, higher coordination numbers have been established, but in some of these there is no evidence for stereochemically active lone pairs as in the 10-coordinate Pb( r -N 03)2(2,9-diformyl-1,10-phenanthrolinedi-semicarbazone). However, in the 1,4,7-triazacyclononane complex, tacnPb(N03)2, the electron pair is stereochemically active. 

In the N,iV, N"-trimethyl-l,4,7-triazacyclononane complex, the molybdenum atom probably assumes a 4 3 piano stool hepta-coordination, similar to that found in the X-ray structure of [Mo([9]aneN3)(CO)3Br] [61]. 

TpMo(CC6H4Me-4)(CO)L (L = CO, PPh3) with CS2733 and S8 in refluxing thf,734 respectively. Bis(pyrazolyl)borate oxo Molv complexes include square pyramidal Bp MoO(S2P Pr2) (j/(Mo=0 980cm ).735 The triazacyclononane complex, (Me3tcn)MoOI2 (327, Scheme 6) has been structurally characterized.326... 

SCHEME 57. One-electron oxidation of phenols by a dimeric Mn(lV/lV) triazacyclononane complex in the presence of H2O2... 

Triazacyclononane complexes, as oxidation catalysts 1209, 1212 Triazines—see Hydroxyphenyltriazines... 

J. Hartman, R. L. Rardin, P. Chaudhviri, K. Pohl, K. Wieghardt, B. Nuber, J. Weiss, G. Papaefthymiou, R. Frankel, and S. Lippard. Synthesis and characterization of (p-hydroxo)bis( A-acetato)diiron(II) and ( j.-oxo)bis( j.-acetato)diiron(III) l,4,7-trimethyl-l,4,7-triazacyclononane complexes as models for binudeeir iron centers in biology properties of the mixed valence diiron(n,ni) species. /. Am. Chem. Soc., 109 7387 (1987). 

Hage, R. and Lienke, A., Bleach and oxidation catalysis by manganese-l,4,7-triazacyclononane complexes amd hydrogen peroxide, J. Mol. Catal. A Chemical, 251 150-158, 2006. 

The use of such flow and/or stopped flow systems has been used quite extensively to investigate the kinetics of radical reactions. These include the use of a stopped flow EPR system to investigate the one-electron oxidation of a range of phenols by a dimeric manganese(rV/TV) triazacyclononane complex with and without hydrogen peroxide. 

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