+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Design of new heteroscorpionate ligands and their coordinative ability toward Group 4 transition metals; an efficient synthetic route to obtain enantiopure ligands



Design of new heteroscorpionate ligands and their coordinative ability toward Group 4 transition metals; an efficient synthetic route to obtain enantiopure ligands



Dalton Transactions 2006(36): 4359-4370



The reaction of different types of bis(pyrazol-1-yl)methane derivatives with Bu(n)Li and alkyl or aryl-containing-isocyanates or isothiocyanates, some of these as chiral reagents, gives rise to the preparation of new heteroscorpionate ligands in the form of the lithium derivatives [Li(NNE)]2 (1-10), although a similar process with trimethylsilyl isocyanate or isothiocyanate gave the complexes [Li(NCX)(bdmpzs)(THF)](X = O, 11; X = S, 12)[bdmpzs = bis(3,5-dimethylpyrazol-1-yl)trimethylsilylmethane]. Compounds 1-8 reacted with [TiCl4(THF)2] or [MCl4](M = Zr, Hf) to give a series of cationic complexes [MCl3{kappa3-NNE(H)}]Cl (13-36) where the heteroscorpionate ligand contains either an acetamide or thioacetamide group resulting from the protonation of the corresponding acetamidate or thioacetamidate. However, under appropriate experimental conditions neutral Ti complexes were isolated-namely [TiClx(NMe2)3-x(S-mbbpam)](37-39)[S-mbbpam =(S)-(-)-N-alpha-methylbenzyl-2,2-bis(3,5-dimethylpyrazol-1-yl)acetamidate]. Finally, two alkoxide-containing titanium complexes [TiClx(OR)3-x(S-mbbpamH)]Cl (40-41) were also prepared. The structures of these complexes have been determined by spectroscopic methods and, in addition, the X-ray crystal structures of 1, 12, and 19 were also established.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 048741009

Download citation: RISBibTeXText

PMID: 16967120

DOI: 10.1039/b605703a


Related references

On the search for NNO-donor enantiopure scorpionate ligands and their coordination to group 4 metals. Inorganic Chemistry 48(12): 5540-5554, 2009

Compounds with low-valent group 13 metals as ligands for electron poor main group and transition metals. Dalton Transactions 2009(11): 1887-1893, 2009

General synthetic route to chiral flexible biphenylphosphine ligands: the use of a chiral additive enables the preparation and observation of metal complexes incorporating the enantiopure form. Organic Letters 3(2): 243-245, 2001

A general synthetic route for the preparation of high-spin molecules: Replacement of bridging hydroxo ligands in molecular clusters by end-on azido ligands. Polyhedron 26(9-11): 2089-2094, 2007

Antibiotics as ligands the coordinating ability of deprotonated cyclo serine towards transition metals. Australian Journal of Chemistry 36(6): 1125-1132, 1983

Design of cyclic peptides as chiral ligands for transition metals. Abstracts of Papers American Chemical Society 208(1-2): ORGN 92B, 1994

Heteroscorpionate ligands based on bis(pyrazol-1-yl)methane: design and coordination chemistry. Dalton Transactions 2004(10): 1499-1510, 2004

A convenient synthetic route to benz[cd]azulenes: versatile ligands with the potential to bind metals in an eta5, eta6, or eta7 fashion. Chemistry 10(21): 5398-5405, 2004

Oxy-functionalization of Group 9 and 10 transition metal methyl ligands: use of pyridine-based hemi-labile ligands. Dalton Transactions 43(20): 7608-7614, 2014

Theoretical investigation of the -bonding ability of P-, S-, and N-containing ligands in group 6 transition metal complexes. Polyhedron 17(8): 1267-1273, 1998

X-ray-absorption studies of the d-orbital occupancies of selected 4d/5d transition metals compounded with group-III/IV ligands. Physical Review. B, Condensed Matter 50(10): 6555-6563, 1994

New synthetic routes toward enantiopure nitrogen donor ligands. Journal of Organic Chemistry 71(25): 9283-9290, 2006

Design of chiral ligands for asymmetric catalysis: from C2-symmetric P,P- and N,N-ligands to sterically and electronically nonsymmetrical P,N-ligands. Proceedings of the National Academy of Sciences of the United States of America 101(16): 5723-5726, 2004

Bis(pyrazol-1-yl)acetates as tripodal heteroscorpionate ligands in iron chemistry: syntheses and structures of iron(II) and iron(III) complexes with bpza, bdmpza, and bdtbpza ligands. Inorganic Chemistry 42(22): 7182-7188, 2003

Synthesis and structural characterization of group 6 transition metal complexes with terminal fluoromethylidyne (CF) ligands; a DFT/NBO/NRT comparison of bonding characteristics of terminal NO, CF and CH ligands. Dalton Transactions 40(1): 47-55, 2010