Cycloaddition reactions of titanium and zirconium imido, oxo and hydrazido complexes supported by tetraaza macrocyclic ligands ‡

Blake, Alexander J.; McInnes, Jacqueline M.; Mountford, Philip; Nikonov, Georgii I.; Swallow, Daniel; Watkin, David J.

doi:10.1039/a806827e

Cited by 114 publications

(142 citation statements)

References 48 publications

(48 reference statements)

Supporting

Mentioning

137

Contrasting

Order By: Relevance

“…1 H NMR (C 6 D 6 , 300.1 MHz, 296K): δ(ppm) 7.32-7.00 (overlapping, 10H total, PhCH 2 N), 4.60 (m, 1H, 3 J H-H = 6 Hz, OCH(CH 3 ) 2 )), 4.49 (m, 1H, 3 J H-H = 6 Hz, OCH(CH 3 ) 2 )), 3.46-3.34 ( and 12H, OCH(CH 3 ) 2 ). 13 (overlapping, CH 2 CH 2 CH 2 and OCH(CH 3 ) 2 ). Anal.…”

Section: {(18-dibenzyl-4-tert-butylisocyanate)cyclam}zr(o I Pr) 2 (5)mentioning

confidence: 97%

“…20H total,PhCH 2 (d, 3 J H-H = 6 Hz, 6H, CH(CH 3 ) 2 ). 13 (4,11-dibenzyl-N 1 -isopropyl-Cyclam-1-thiocarboxamidato)Zr(O i Pr) 2 (7): At room temperature, addition of one equivalent of i PrNCS (9 µL, 0.08 mmol) to a C 6 D 6 solution of 2 (48 mg, 0.08 mmol) led to the quantitative formation of complex 7 as revealed by 1 H and 13 (d, 3 J H-H = 6 Hz 3H, OCH(CH 3 ) 2 ), 1.29 (d, 3 J H-H = 6 Hz, 3H, OCH(CH 3 ) 2 ), 1.26 (d, 3 J H-H = 6 Hz, 3H, OCH(CH 3 ) 2 ). 13 26.8 (C 6 H 11 N), 26.7 (CH 2 CH 2 CH 2 ), 25.7 (C 6 H 11 N or CH 2 CH 2 CH 2 ), 25.6 (C 6 H 11 N or CH 2 CH 2 CH 2 ).…”

Section: {(18-dibenzyl-4-tert-butylisocyanate)cyclam}zr(o I Pr) 2 (5)mentioning

confidence: 97%

“…1.12 (m, 2H, CH 2 CH 2 CH 2 ). 13 (16). The compound was obtained as described for 15 heating the reaction mixture at 60ºC.…”

Section: {(18-dibenzyl-4-tert-butylisocyanate)cyclam}zr(o I Pr) 2 (5)mentioning

confidence: 99%

See 2 more Smart Citations

Reactions of heteroallenes with cyclam-based Zr(iv) complexes

et al. 2015

View full text Add to dashboard Cite

This work describes reactions of heteroallenes with diamido-diamine cyclam-based Zr(iv) complexes of the general formula (Bn2Cyclam)ZrX2 (X = O(t)Bu, , O(i)Pr, , SPh, , NH(t)Bu, ) as well as the di-orthometallated species ((C6H4CH2)2Cyclam)Zr, . The reactions of isocyanates or isothiocyanates with , or resulted in the formation of N-bonded ureate or thioureate cyclam complexes upon [2 + 2] cycloaddition of the Zr-Namido bonds of the cyclam to the heteroallene (). DFT calculations showed that κ(2)-N,N'-ureate bonding is favoured over κ(2)-N,O-ureates, which in turn may be formed in reactions with bulky isocyanates as 1-naphthyl isocyanate (NpN[double bond, length as m-dash]C[double bond, length as m-dash]O). The reactions of with N,N'-cyclohexylcarbodiimide (CyN[double bond, length as m-dash]C[double bond, length as m-dash]NCy) and carbon disulfide afforded guanidinate and dithiocarbamate fragments, respectively, appended to one of the nitrogen atoms of the cyclam ligand. These reactions represent a reliable method for the synthesis of asymmetrically N-functionalized cyclams giving rise to C1 symmetry Zr(iv) species by addition of one equivalent of heteroallenes. The reaction of (Bn2Cyclam)Zr(NH(t)Bu)2, , with one equivalent of mesityl isocyanate (MesN[double bond, length as m-dash]C[double bond, length as m-dash]O) also proceeds through insertion, involving one Zr-NH(t)Bu bond. However, it was observed that the reaction of (Bn2Cyclam)Zr(NH(t)Bu)2, , with MesN[double bond, length as m-dash]C[double bond, length as m-dash]O follows a different path if the reaction is carried out at 60 °C. In this case the reaction leads to [2 + 2] addition of the Zr-Ncyclam bond to the isocyanate, with a concomitant occurrence of orthometallation of the one benzyl pending group of the cyclam ring. The reaction of (t)BuN[double bond, length as m-dash]C[double bond, length as m-dash]O with the di-orthometallated complex ((C6H4CH2)2Cyclam)Zr, , also gave a κ(2)-N,N'-ureate fragment, by isocyanate addition to the macrocycle. DFT calculations on these systems were conducted in an attempt to rationalise the reactivity patterns observed.

show abstract

Section: {(18-dibenzyl-4-tert-butylisocyanate)cyclam}zr(o I Pr) 2 (5)mentioning

confidence: 97%

Section: {(18-dibenzyl-4-tert-butylisocyanate)cyclam}zr(o I Pr) 2 (5)mentioning

confidence: 97%

See 1 more Smart Citation

Reactions of heteroallenes with cyclam-based Zr(iv) complexes

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The reaction of 1a · THF with tert ‐butylisocyanate yields di‐ tert ‐butylcarbodiimide and oligomeric [Cp 2 ZrO] n , presumably by cycloreversion of the transient N,O‐bound isocyanate cycloadduct 30 (Scheme ) 6. The Mountford30 and Woo31 groups have isolated both N,N‐ and N,O‐bound isocyanate cycloadducts of imidozirconium complexes, the latter of which were demonstrated to slowly extrude carbodiimide with concomitant formation of oxozirconium products 31. Reaction of 1a · THF with 1.5 equiv of diphenylketene gives the expected organic imido/oxo exchange product, ketenimine 31 ; however, the Zr‐containing byproduct is the unusual bimetallic (μ‐oxo)(μ‐enediolato) complex 32 (Scheme ) 28.…”

Section: Resultsmentioning

confidence: 99%

A case of acute myocardial infarction treated with a new thrombectomy system

Nishida

Nakamura

Tsunoda

et al. 2002

Cathet Cardio Intervent

View full text Add to dashboard Cite

show abstract

“…The chemistry of macrocyclic complexes has received much attention in recent years on account of its various applications in bioinorganic chemistry [2,3]. Transition metal complexes with macrocyclic ligands are well known for their enhanced kinetic and thermodynamic stability [4][5][6][7][8][9][10][11][12][13][14]. Many tetradentate Schiff bases are known to stabilize unusual oxidation states of the coordinated metal [15][16][17][18][19].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and structural characterization of a fully conjugated macrocyclic tetraaza(14)-membered Schiff base and its bivalent metal complexes

Raman¹,

Thangaraja²

2005

Transition Met Chem

View full text Add to dashboard Cite

A novel 14-membered macrocyclic Schiff base derived from 3-cinnamalideneacetoacetanilide and o-phenylenediamine acts as a tetradentate and strongly conjugated ligand to form a cationic solid complex with CuCl 2 /NiCl 2 / CoCl 2 /ZnCl 2 . The ligand and the complexes were characterized by the usual spectral and analytical techniques. The main i.r. band of the macrocyclic Schiff base was compared to that of its metal complexes. The C@N bands are shifted to the lower wave number. The cyclic voltammogram of the copper complex shows that the macrocyclic ligand is able to stabilize the copper(III) oxidation state. The e.s.r. spectra of the copper complex in DMSO solution at room temperature and liquid N 2 temperature were recorded and their salient features thoroughly discussed. The antimicrobial screening tests were also recorded and gave good results in the presence of metal ions in the ligand system.

show abstract

Cycloaddition reactions of titanium and zirconium imido, oxo and hydrazido complexes supported by tetraaza macrocyclic ligands ‡

Cited by 114 publications

References 48 publications

Reactions of heteroallenes with cyclam-based Zr(iv) complexes

Reactions of heteroallenes with cyclam-based Zr(iv) complexes

A case of acute myocardial infarction treated with a new thrombectomy system

Synthesis and structural characterization of a fully conjugated macrocyclic tetraaza(14)-membered Schiff base and its bivalent metal complexes

Contact Info

Product

Resources

About