(S)-tert-butyl 2-(4-(6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalen-2-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate
[CAS# 1228552-26-8]

Identification

• Classification: Organic raw materials >> Carboxylic compounds and derivatives >> Carboxylic esters and their derivatives
• Name: (S)-tert-butyl 2-(4-(6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalen-2-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate
• Synonyms: tert-butyl (2S)-2-[5-[6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalen-2-yl]-1H-imidazol-2-yl]pyrrolidine-1-carboxylate
• Molecular Formula: C₂₈H₃₆BN₃O₄
• Molecular Weight: 489.41
• CAS Registry Number: 1228552-26-8
• SMILES: B1(OC(C(O1)(C)C)(C)C)C2=CC3=C(C=C2)C=C(C=C3)C4=CN=C(N4)[C@@H]5CCCN5C(=O)OC(C)(C)C

Properties

• Density: 1.2±0.1 g/cm³ Calc.^*
• Boiling point: 683.8±55.0 ºC 760 mmHg (Calc.)^*
• Flash point: 367.3±31.5 ºC (Calc.)^*
• Index of refraction: 1.599 (Calc.)^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Discovory and Applicatios

(S)-tert-butyl 2-(4-(6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalen-2-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate is a complex, chiral organic compound that has been developed as a synthetic intermediate for constructing functional molecules, particularly in pharmaceutical research and materials science. It incorporates several distinct structural motifs that make it a valuable building block in organic synthesis, notably a boronic ester group, an imidazole heterocycle, a substituted naphthyl ring, and a stereodefined pyrrolidine unit protected with a tert-butyl carbamate.

The discovery of this compound is tied to the broader development of organoboron chemistry, especially the use of boronic esters such as pinacol boronate derivatives for cross-coupling reactions. The 4,4,5,5-tetramethyl-1,3,2-dioxaborolane group is a well-known boronic ester that provides high stability, ease of purification, and compatibility with Suzuki-Miyaura coupling reactions. This reaction is among the most widely employed carbon-carbon bond-forming reactions in modern organic chemistry and has enabled the efficient synthesis of biaryl motifs and other complex frameworks found in drugs, agrochemicals, and functional materials.

The incorporation of a naphthyl unit functionalized at the 6-position with the boronic ester group provides both steric bulk and extended π-conjugation, which are useful for modulating molecular recognition properties or fine-tuning photophysical behavior. This naphthyl core, substituted further by the imidazole moiety, enhances the structural rigidity and facilitates interactions in receptor binding pockets or in electronic materials.

The imidazole ring, a five-membered nitrogen heterocycle, is known for its biological relevance and chemical reactivity. It can act as both a base and a nucleophile, and it often serves as a coordinating group in metal complexes or as part of active pharmacophores. The 2-position of the imidazole in this compound is bonded to the chiral pyrrolidine ring, whose nitrogen is protected by a tert-butyl carbamate (Boc) group. This Boc group is widely used in peptide and medicinal chemistry to temporarily mask amines during multistep synthesis. It is stable under basic and mildly acidic conditions and can be cleaved under stronger acidic conditions such as trifluoroacetic acid treatment.

The (S)-configuration at the 2-position of the pyrrolidine ring is significant in drug discovery, as chirality influences the bioactivity, metabolism, and toxicity of compounds. Enantiomerically pure pyrrolidines have been utilized in the development of enzyme inhibitors, ligands for asymmetric catalysis, and chiral auxiliaries in synthesis. The presence of this stereocenter in the current molecule suggests its use in enantioselective synthesis or as a chiral intermediate for further elaboration into biologically active molecules.

Applications of this compound are mainly found in synthetic organic chemistry. Its boronic ester function allows for Suzuki coupling with aryl or vinyl halides, enabling the formation of diverse biaryl linkages while preserving stereochemical integrity. This makes the compound a strategic intermediate for the synthesis of pharmaceutical candidates or molecular probes, particularly where control of stereochemistry and functional group compatibility are critical. Additionally, the extended π-system of the naphthyl and imidazole framework may offer photophysical properties useful in sensor design or materials applications.

From a synthetic perspective, this molecule is typically accessed by first preparing the imidazole-linked naphthalene derivative, followed by selective borylation at the 6-position of the naphthyl ring. The borylation step is often carried out using Ir- or Pd-catalyzed C-H activation methods or through lithiation followed by trapping with a boron reagent such as bis(pinacolato)diboron. The Boc-protected (S)-pyrrolidine moiety is then introduced through nucleophilic substitution, alkylation, or cross-coupling strategies under conditions that retain stereochemical fidelity.

This compound is generally handled as a solid and is soluble in common organic solvents like tetrahydrofuran, dichloromethane, and dimethylformamide. It should be stored under an inert atmosphere to avoid degradation of the boronic ester moiety, which can hydrolyze upon exposure to moisture. Standard safety protocols should be observed when working with organoboron and heterocyclic compounds, including the use of personal protective equipment and working within a fume hood.

In summary, (S)-tert-butyl 2-(4-(6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)naphthalen-2-yl)-1H-imidazol-2-yl)pyrrolidine-1-carboxylate is a multifunctional, stereodefined synthetic intermediate valuable for constructing complex molecules through palladium-catalyzed cross-coupling and for exploring structure-activity relationships in drug design and material science.