Recyclable chiral Cu(II) macrocyclic salen complex catalyzed enantioselective aza-Henry reaction of isatin derived N-Boc ketimines and its application for the synthesis of β-diamine

Menapara, Tusharkumar; Choudhary, Manoj K.; Tak, Rajkumar; Kureshy, Rukhsana I.; Khan, Noor‐ul H.; Abdi, Sayed H. R.

doi:10.1016/j.molcata.2016.05.021

Cited by 13 publications

(6 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[62] Here, the catalyst with the flexible longer ethyleneglycol linker showed best results in term of yield (up to 92 %) and selectivity (up to 98 % ee) compared to other shorter or more rigid links, indicating the important role of flexibility in the enantioselective catalytic environment. The same flexibility was also crucial for the aza-Henry reaction of various isatinderived N-Boc ketimines with nitroalkanes, catalyzed by macrocyclic Cu-salen complexes, prepared in situ, [63] suggesting an efficient cooperativity of the two catalytic units. Accordingly, Kureshy et al have synthesized [H 4 ]-salen derivatives by reduction of chiral dimeric macrocyclic salen ligands with NaBH 4 .…”

Section: Macrocyclic Salen Complexesmentioning

confidence: 91%

Chiral Salen Complexes for Asymmetric Heterogeneous Catalysis: Recent Examples for Recycling and Cooperativity

2019

View full text Add to dashboard Cite

Chiral salen complexes are privileged and versatile catalysts used in a wide variety of enantioselective transformations. Researches for their use in multicatalysis, including cooperative as well as tandem processes, are more recent, but many reports already highlight the important effect of the salen ligand structure on reaction rates and/or selectivities. This review article thus outlines the literature covering last five years, on the current developments of chiral polymetallic salen complexes used in asymmetric heterogeneous catalysis; their preparation, their efficiency as catalysts in various reactions and their recyclability are highlighted according to the immobilization procedures involved for their heterogenization. These methods include grafting on organic or inorganic supports insuring easy recovery by simple filtration. Polymerization processes are also part of recent research, leading to high densities of catalytic sites to favor their cooperativity. Combination of salen complexes via non covalent interactions or their introduction on MOFs and COFs networks is currently in full expansion, with examples of highly functionalized and enantioenriched products issued from tandem catalysis.

show abstract

Section: Macrocyclic Salen Complexesmentioning

confidence: 91%

Chiral Salen Complexes for Asymmetric Heterogeneous Catalysis: Recent Examples for Recycling and Cooperativity

2019

View full text Add to dashboard Cite

show abstract

“…The reduced form of this kind of macrocycles, i.e., rhombamines was applied in NMR enantiodiscrimination of chiral carboxylic acids and their derivatives [61,62]. The condensation of enantiopure DACH or DPEN with aromatic dialdehydes containing two phenol fragments results in the formation of the extended [2 + 2] imines 20, 21, 24-26, which can also be transformed into their reduced amine forms 22 and 23 (Figure 10) [63][64][65][66][67][68][69][70]. These enantiopure ligands contain two compartments corresponding to the chiral salen environment (the parent macrocycle 26 was called calixsalen [63]).…”

Section: [2 + 2] Macrocyclesmentioning

confidence: 99%

“…The energy-minimized structure of such a dinuclear complex shows a plausible intermediate in the catalytic cycle, where the epichlorohydrin molecule is bound in the center of the expanded macrocycle between the two cobalt(III) ions [64]. The extended tetraphenolic macrocycles 20-26 are predisposed to form dinuclear complexes with transition metals, such as cobalt(III), copper(II), vanadium(V), manganese(III) or titanium(IV), which exhibit interesting enantioselective catalytic activity in the kinetic resolution of epoxides [64], Henry reaction [65], aza-Henry reaction [70], Strecker reaction [67], O-acetylcyanation/cyanoformylation of aldehydes [66], asymmetric carbonylation of aldehydes [68], and epoxidation of alkenes [69]. The dinuclear copper(II) complex of another tetraphenolic [2 + 2] imine derived from DPEN was active as an enantioselective catalyst in the Henry reaction [71].…”

Section: [2 + 2] Macrocyclesmentioning

confidence: 99%

“…with transition metals, such as cobalt(III), copper(II), vanadium(V), manganese(III) or titanium(IV), which exhibit interesting enantioselective catalytic activity in the kinetic resolution of epoxides [64], Henry reaction [65], aza-Henry reaction [70], Strecker reaction [67], O-acetylcyanation/cyanoformylation of aldehydes [66], asymmetric carbonylation of aldehydes [68], and epoxidation of alkenes [69]. The dinuclear copper(II) complex of another tetraphenolic [2 + 2] imine derived from DPEN was active as an enantioselective catalyst in the Henry reaction [71].…”

Section: [2 + 2] Macrocyclesmentioning

confidence: 99%

See 1 more Smart Citation

Imine- and Amine-Type Macrocycles Derived from Chiral Diamines and Aromatic Dialdehydes

Lisowski

2022

Molecules

View full text Add to dashboard Cite

The condensation of aromatic dialdehydes with chiral diamines, such as 1,2-trans-diaminocyclohexane, leads to various enantiopure or meso-type macrocyclic Schiff bases, including [2 + 2], [3 + 3], [4 + 4], [6 + 6] and [8 + 8] condensation products. Unlike most cases of macrocycle synthesis, the [3 + 3] macrocycles of this type are sometimes obtained in high yields by direct condensation without a metal template. Macrocycles of other sizes from this family can often be selectively obtained in high yields by a suitable choice of metal template, solvent, or chirality of the building blocks. In particular, the application of a cadmium(II) template results in the expansion of the [2 + 2] macrocycles into giant [6 + 6] and [8 + 8] macrocycles. These imine macrocycles can be reduced to the corresponding macrocyclic amines which can act as hosts for the binding of multiple cations or multiple anions.

show abstract

“…33 Abdi's group obtained wonderful diastereoselectivity (up to 98:2) of chiral Cu(II) macrocyclic salen complexes with isatinderived ketimines. 34 N4 complex 35 with isatin-derived ketimines. Compared with metal catalytic systems, organocatalysis with low toxicity, low cost, easy preparation, and good stability have great potential in organic chemistry.…”

Section: ■ Introductionmentioning

confidence: 99%

Novel Chiral Thiourea Derived from Hydroquinine and l-Phenylglycinol: An Effective Catalyst for Enantio- and Diastereoselective Aza-Henry Reaction

et al. 2021

View full text Add to dashboard Cite

A series of chiral thiourea bearing multiple H-bond donors derived from hydroquinine has been reported. The aza-Henry reaction of isatin-derived ketimines and long-chain nitroalkanes catalyzed by these chiral thioureas can achieve high enantioselectivity (78−99% ee) and excellent diastereoselectivity (up to 99:1). This work is the first report on long-chain nitroalkanes as substrates with excellent diastereoselectivity in metal-free catalytic systems.

show abstract

Recyclable chiral Cu(II) macrocyclic salen complex catalyzed enantioselective aza-Henry reaction of isatin derived N-Boc ketimines and its application for the synthesis of β-diamine

Cited by 13 publications

References 24 publications

Chiral Salen Complexes for Asymmetric Heterogeneous Catalysis: Recent Examples for Recycling and Cooperativity

Chiral Salen Complexes for Asymmetric Heterogeneous Catalysis: Recent Examples for Recycling and Cooperativity

Imine- and Amine-Type Macrocycles Derived from Chiral Diamines and Aromatic Dialdehydes

Novel Chiral Thiourea Derived from Hydroquinine and l-Phenylglycinol: An Effective Catalyst for Enantio- and Diastereoselective Aza-Henry Reaction

Contact Info

Product

Resources

About