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Shreeyukta Singh

Publications and source records attributed to Shreeyukta Singh.

5 recordsLinked to original sources
PubMed2006

Syntheses of highly fluorinated 1,3,5-triazapentadienyl ligands and their use in the isolation of copper(I)-carbonyl and copper(I)-ethylene complexes.

Fully fluorinated triazapentadienyl ligand [N{(C3F7)C(C6F5)N}2]- and the related [N{(C3F7)C(2-F,6-(CF3)C6H3)N}2]- have been synthesized in good yield via a convenient route and used in the isolation of three- and four-coordinate copper(I)-carbon monoxide complexes. They show fairly high nu(CO) values (>2100 cm(-1)), indicating the presence of electron-poor Cu sites. The copper(I)-ethylene adduct [N{(C3F7)C(C6F5)N}2]Cu(C2H4), featuring a three-coordinate Cu site, has also been synthesized using [N{(C3F7)C(C6F5)N}2]CuNCCH3 and C2H4.

Journal Article↗
PubMed2006

Monomeric lithium triazapentadienyl complexes.

Treatment of 1,3,5-triazapentadienes [N{(C3F7)C(Mes)N}2]H and [N{(C3F7)C(Dipp)N}2]H (where Mes = 2,4,6-Me3C6H2; Dipp = 2,6-Pr(i)2C6H3) with n-BuLi in hexane, followed by the crystallization from hexane-THF mixture afforded the corresponding lithium 1,3,5-triazapentadienyl complexes as their THF solvates. X-Ray crystallographic analyses revealed that [N{(C3F7)C(Mes)N}2]Li(THF)2 and [N{(C3F7)C(Dipp)N}2]Li(THF) are monomeric in the solid state. [N{(C3F7)C(Mes)N}2]Li(THF)2 has a four-coordinate lithium center with a distorted tetrahedral geometry, and features a boat-shaped C2N3Li metallacycle. [N{(C3F7)C(Dipp)N}2]Li(THF) has a three-coordinate lithium atom and a planar, U-shaped C2N3 ligand backbone. The synthesis, solid-state structure, and 1H and 19F NMR spectroscopic details of [N{(C3F7)C(Mes)N}2]H are also reported.

Aza Compounds↗
PubMed2004

Silver(I) complexes of a sterically demanding fluorinated triazapentadienyl ligand [N((C3F7)C(Dipp)N)2]- (Dipp = 2,6-diisopropylphenyl).

Sterically demanding triazapentadiene [N((C3F7)C(Dipp)N)2]H affords the isolation of thermally stable, two- and three-coordinate silver complexes. The free ligand [N((C3F7)C(Dipp)N)2]H has a W-shaped ligand backbone in the solid state.[N((C3F7)C(Dipp)N)2]H reacts with silver(I) oxide in acetonitrile leading to CH(3)CNAg [N((C3F7)C(Dipp)N)2]HIt features a two-coordinate silver center and a kappa(1)-coordinated triazapentadienyl ligand. This silver acetonitrile complex serves as an excellent precursor to obtain thermally stable, silver isocyanide t-BuNCAg [N((C3F7)C(Dipp)N)2]Hand silver phosphine [[N((C3F7)C(Dipp)N)2]HAgPPh(3) adducts. IR spectroscopic data for the silver(I) isocyanide t-BuNCAg [N((C3F7)C(Dipp)N)2]Hshows nu(CN) at 2219 cm(-)(1). The silver ion coordinates to the triazapentadienyl ligand via the central nitrogen atom. The silver PPh(3) adduct,[N((C3F7)C(Dipp)N)2]HAgPPh(3), was synthesized by treating CH3CNAg [N((C3F7)C(Dipp)N)2]Hwith PPh(3). It displays relatively large Ag-P coupling in the (31)P NMR spectrum. The triazapentadienyl ligand in[N((C3F7)C(Dipp)N)2]HAgPPh(3) acts as a chelating kappa(2)-donor. The Ag-P bond is relatively short (2.3487(10) A).

Journal Article↗
PubMed2004

Copper(I) complexes of fluorinated triazapentadienyl ligands: synthesis and characterization of [N[(C3F7)C(Dipp)N]2]CuL (where L = NCCH3, CNBut, CO; Dipp = 2,6-diisopropylphenyl).

Sterically demanding triazapentadiene [N[(C3F7)C(Dipp)N]2] H has been synthesized in good yield. It features a W-shaped ligand backbone in the solid state. [N[(C3F7)C(Dipp)N]2]H reacts with copper(I) oxide in acetonitrile leading to [N[(C3F7)C(Dipp)N]2]CuNCCH3. This copper adduct serves as an excellent precursor to obtain thermally stable [N[(C3F7)C(Dipp)N]2]CuCNBut and [N[(C3F7)C(Dipp)N]2]CuCO. IR spectroscopic data of these copper(I) isocyanide (CN = 2176 cm(-1)) and copper(I) carbonyl (CO = 2109 cm(-1)) complexes indicate that the [N[(C3F7)C(Dipp)N]2]- ligand is a fairly weak donor.

Journal Article↗