A 2‐Anilidomethylpyridine Ligand Framework Showcasing Hydride Storage and Transfer Abilities in Its Aluminum Chemistry

Mandal, Chhotan; Kundu, Abhishek; Das, Sanjay; Adhikari, Debashis; Mukherjee, Debabrata

doi:10.1002/chem.202301119

Cited by 2 publications

(2 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is thus clear that an “acid-free” approach would be necessary to circumvent NN L’s reactive nature. Freshly prepared [ZnH 2 ] ∞ is thus considered to begin with for possibly a direct access to [( NN L)ZnH] either by deprotonating NN L H or by inserting into its imine precursor . But in both cases, no reaction takes place at room temperature, while mild heating leads to the thermal decomposition of [ZnH 2 ] ∞ itself .…”

Section: Results and Discussionmentioning

confidence: 99%

“…But the course of investigation interestingly and for the first time reveals the reactive nature of this framework’s anilide backbone toward electrophiles like Brønsted and Lewis acids, even in preference over the Zn’s terminal position. For the record, our recently reported Al chemistry on the same ligand derivative divulges for the first time its susceptibility toward a nucleophilic hydride insertion at the pyridyl’s para -position …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone’s Reactive Nature

Mandal,

Joshi,

Das

et al. 2023

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

Low-coordinate heteroleptic zinc hydrides are catalytically important but rare and synthetically challenging. We herein report three-coordinate monomeric zinc hydride on a 2anilidomethylpyridine framework ( NN L). The synthetic success comes through systematically screening a few different routes from different precursors. During the process, the ligand's anilide backbone interestingly appears to be more reactive than Zn's terminal site to electrophilic Lewis and Brønsted acids. The proligand NN LH reacts with [Zn{N(SiMe 3 ) 2 } 2 ] and ZnEt 2 to give [( NN L)ZnA] (A = N(SiMe 3 ) 2 (1), Et(2)). Both are inert to PhSiH 3 and H 2 but react with HBpin only through the internal Zn−N anilide bond to give the borylated ligand NN LBpin (3). The reactions of 1 and 2 with Ph 3 EOH (E = C, Si) afford a series of divergent compounds like [( NN LH)Zn(OSiPh 3 ) 2 ] (4), [Zn 3 (OSiPh 3 ) 4 Et 2 ] (5), and [EtZn(OCPh 3 )] (6). But in all cases, it is invariably the Zn−N anilide bond protonated by the −OH with equal or higher preference than the terminal Zn−N or Zn−C bonds. A DFT analysis rationalizes the origin of such a reactivity pattern. Realizing that an acidfree route might be the key, reacting [( NN L)Li] with ZnBr 2 gives [( NN L)Zn(μ-Br)] 2 (7), which on successively treating with KOSiPh 3 and PhSiH 3 gives the desired [( NN L)ZnH] (8) as a three-coordinate monomer with a terminal Zn−H bond. Estimating the ligand steric in 8 shows the openness in Zn's coordination sphere, a desired criterion for efficient catalysis. This and a positive influence of the pyridyl sidearm is reflected in 8's superior activity in hydroborating PhC(O)Me by HBpin in comparison to Jones' two-coordinate anilido zinc hydride.

show abstract

Section: Results and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone’s Reactive Nature

Mandal,

Joshi,

Das

et al. 2023

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

Heteroleptic Magnesium n-Butyl on a Chemically Non-innocent 2-Anilidomethylpyridine Ligand Leading to Diverse Magnesium Hydrides

Mandal,

Joshi,

Mishra

et al. 2024

Inorg. Chem.

View full text Add to dashboard Cite

Molecular magnesium hydrides and hydride-rich clusters are of significant interest for applications ranging from catalysis and small molecule activation to hydrogen storage. Here, we investigate the 2-anilidomethylpyridine framework NNL as an ancillary support for magnesium organometallics with a special emphasis on hydrides. The proligand NNLH (N-[2,6-bis(1-methylethyl)phenyl]-α,6-diphenyl-2-pyridinemethanamine) gives [(NNL)Mg( n Bu)(thf)] (1) by n butane elimination from Mg( n Bu)2(thf) n . A stronger donor such as DMAP replaces the THF from 1 to give [(NNL)Mg( n Bu)(dmap)] (2). Both are air-sensitive, and 1 is adventitiously oxidized into [(NNL)Mg(μ-O n Bu)]2 (3 2 ). The homoleptic [(NNL)2Mg] (8) is made from 1 and a second equiv of NNLH. 1’s terminal n Bu group is selectively protonated by HN(SiMe3)2 to give [(NNL)MgHMDS] (4; HMDS = N(SiMe3)2), whereas Ph3SiOH partially protonates the backbone anilide as well to give a mixture of [(NNL)Mg(OSiPh3)(thf)] (5) and free NNLH. Like HN(SiMe3)2, aprotic MeOTf also reacts by selectively abstracting the n Bu group from 1 to give [(NNL)Mg(μ:κ2-O,O’-OTf)(thf)]2 (6 2 ). Interestingly, screening the common synthetic routes for magnesium hydrides leads to diverse outcomes upon varying the Mg precursors and hydride sources. 1 and PhSiH3 give the hydride cluster [{(NNL)2Mg2(μ-H)}2(μ-H)4Mg] (7), whereas 2 and PhSiH3 give the molecular complex [(NNLde)Mg(dmap)2] (9) with a dearomatized pyridyl backbone. 1 and HBpin (pinacolborane) give a product mixture, from which a different hydride cluster [(NNL)2Mg2(μ-H)}2(μ:κ2-O,O’-O2C2Me4)] (10) is identified, showing a rare instance of complete deborylation of a HBpin molecule. 1 and HBcat (catecholborane) also give a product mixture, one of which is the borylated ligand [(NNL)Bcat] (11). HBpin with 4 as the Mg precursor takes the ligand borylation route more selectively to give [(NNL)Bpin] (12). Last, 1 reacts with i PrNH2BH3 to give [(NNL)Mg{NH( i Pr)BH3}] (13), which shows a slow and fractional conversion into the dinuclear mixed hydrido amidoborane [(NNL)2Mg2(μ-H){(μ-NH( i Pr)BH3}] (14) by partial β-hydride elimination. In comparison, [(NNL)Mg( i PrNHBH3)(dmap)] (15) arising from the DMAP-bound 2 and i PrNH2BH3 is stable toward such elimination.

show abstract

A 2‐Anilidomethylpyridine Ligand Framework Showcasing Hydride Storage and Transfer Abilities in Its Aluminum Chemistry

Cited by 2 publications

References 72 publications

2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone’s Reactive Nature

2-Anilidomethylpyridine-Derived Three-Coordinate Zinc Hydride: The Journey Unveils Anilide Backbone’s Reactive Nature

Heteroleptic Magnesium n-Butyl on a Chemically Non-innocent 2-Anilidomethylpyridine Ligand Leading to Diverse Magnesium Hydrides

Contact Info

Product

Resources

About