Cross‐Aldol Reaction of Isatin with Acetone Catalyzed by Leucinol: A Mechanistic Investigation

Abstract

Protein‐metal interactions—traditionally regarded for roles in metabolic processes—are now known to enhance the performance of certain biogenic materials, influencing properties such as hardness, toughness, adhesion, and self‐healing. Design principles elucidated through thorough study of such materials are yielding vital insights for the design of biomimetic metallopolymers with industrial and biomedical applications. Recent advances in the understanding of the biological structure–function relationships are highlighted here with a specific focus on materials such as arthropod biting parts, mussel byssal threads, and sandcastle worm cement.

Towards a Series of Chiral Primary Amines Bearing α-Amino Acid and Benzo[d]imidazole Pendants, and Their Application in Asymmetric Aldol Reactions

“…As a first step, primary amine 5 reacts with ketone 7 to form an enamine intermediate. In principle, and according to a recent mechanistic investigation by Kočovský and coworkers, 29 both the synand anti-rotamers 14 and 15 can be envisaged. Whereas the anti-enamine 15 is kinetically favored, the syn-enamine 14 is thermodynamically more stable and, under equilibrium conditions, the subsequent aldol process will proceed mainly via 14.…”

A New Insight into the Stereoelectronic Control of the Pd0‐Catalyzed Allylic Substitution: Application for the Synthesis of Multisubstituted Pyran‐2‐ones via an Unusual 1,3‐Transposition

“…To gain credence for the qualitative orbital considerations and to elucidate the mechanism in detail,a ssess the validity of the stereoelectronic arguments, and characterize the intermediates and transition states, quantum chemical calculations were carried out for three representative cases, namely af acile versus less efficient reaction (3d!6d vs. 3j!6j)a nd absence of reactivity (3u!6u). Ac omputational approach similar to that employed by us previously, [23] was used (see the computational details section below) with the difference that we obtained electronic energies [E el (QM) in Eq. (1) Figure S2 in the Supporting Information for the TPSSh-D3/COSMO-RS reactionp rofiles)-with the exception of the Pd(TFP) 3 /Pd(TFP) 4 pre-equilibrium discussed below and to as maller extent binding of the reactantt ot he Pd(TFP) 3 catalyst.…”

A Continuous‐Flow Route to Enantioenriched 3‐Substituted‐3‐Hydroxyoxindoles: Organocatalytic Aldol Reactions of Isatin with Acetone

“…One of the most efficient ways for accessing this desirable scaffold is via organocatalysed aldol condensation of a ketone with an isatin derivative. While there have been several organocatalysts reported for this reaction, the leucinol catalysed cross aldol reaction of isatin with acetone in CH 2 Cl 2 solvent reported by Malkov and co‐workers [19–21] provided arguably one of the most efficient route for accessing enantiopure 3‐substituted‐3‐hydroxyoxindole derivatives at ambient temperature. In their work, they demonstrated leucinol to be a simple and cost‐effective organic catalyst.…”