Buy high-quality intermediate from China manufacturer

4-Ethynylpyridine hydrochloride (C₇H₆ClN, MW 139.58 g/mol) is the hydrochloride salt of 4-ethynylpyridine, featuring a terminal alkyne group at the para position of a pyridine ring stabilized by the chloride counterion. Structurally, 4-Ethynylpyridine hydrochloride comprises a pyridine nitrogen capable of metal coordination, paired with an ethynyl group that serves as a versatile handle for cross‑coupling and click chemistry transformations. The para substitution geometry is critical for constructing linear rigid‑rod bidentate ligands (e.g., 1,4‑bis(pyridin‑4‑ylethynyl)benzene) used in metal‑organic frameworks (MOFs) and metallosupramolecular architectures — properties that 2‑ or 3‑ethynyl isomers cannot replicate due to their different spatial arrangements. The hydrochloride salt form of 4-Ethynylpyridine hydrochloride enhances stability and water solubility compared to the free base (CAS 2510‑22‑7), making it the preferred form for synthetic and materials science applications.

2-[(3-Methylbenzyl)oxy]benzaldehyde (C₁₅H₁₄O₂, MW 226.27 g/mol) is an aromatic aldehyde featuring a benzaldehyde core connected via an ether linkage to a 3-methylbenzyl (meta-methylbenzyl) substituent. Structurally, the molecule comprises a salicylaldehyde-derived aromatic ring substituted at the ortho position with a 3-methylbenzyloxy (–O–CH₂–C₆H₄–CH₃) group. The presence of both an electrophilic aldehyde carbonyl and an electron-donating ether oxygen creates a polarized electronic environment that enables diverse chemical transformations. The meta‑methyl group on the pendant benzyl ring introduces additional steric and electronic modulation, making 2-[(3-Methylbenzyl)oxy]benzaldehyde a finely tuned synthetic building block for medicinal chemistry and organic synthesis research. The molecular scaffold is recognized in the literature for its role as a molecular probe targeting glutamine transporter proteins, a property that positions 2-[(3-Methylbenzyl)oxy]benzaldehyde at the interface of chemical synthesis and cancer biology research.

The product is 2-Methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenol, a bifunctional aromatic building block that combines a free phenolic hydroxyl group with a pinacol boronate ester on the same ring. The phenol is located meta to the boronate and ortho to a methyl group, creating a sterically and electronically differentiated scaffold. The pinacol ester provides a robust Suzuki handle, while the unprotected phenol can participate in O‑alkylation, Mitsunobu reactions, or serve as a hydrogen‑bond donor. This dual functionality allows the construction of complex biaryl architectures with a phenol anchor point for further elaboration.

The product is 2-(2,6-dimethylphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, a sterically hindered arylboronic pinacol ester in which a 2,6‑dimethylphenyl group is directly attached to boron. The two ortho‑methyl substituents create significant steric bulk around the carbon–boron bond, retarding protodeboronation and imposing a specific orientation after cross‑coupling. This reagent is the preferred partner for introducing the 2,6‑dimethylphenyl motif — a lipophilic, metabolically stable aromatic ring — into biaryl drug candidates, agrochemicals, and organic materials.

The product is 3-Azaspiro[5.5]undec-7-ene-3-carboxylic acid, 9-oxo-, phenylMethyl ester, a spirocyclic building block that combines a piperidine‑fused cyclohexenone framework with a benzyl carbamate (Cbz) protecting group on the piperidine nitrogen. The spiro[5.5]undec‑7‑ene core provides a rigid, three‑dimensional structure with a Michael‑acceptor enone and a protected secondary amine. This arrangement makes it a versatile intermediate for constructing complex alkaloid‑like scaffolds where the enone can undergo nucleophilic attack, cycloaddition, or reduction, and the Cbz group can be cleanly removed to reveal a free amine.

5′-O-DMTr-5-iodo-2′-dU-3′-CED phosphoramidite (C₃₉H₄₆IN₄O₈P, MW 856.68 g/mol) is a purine nucleoside analog and a modified deoxyuridine phosphoramidite building block for oligonucleotide synthesis. Structurally, 5′-O-DMTr-5-iodo-2′-dU-3′-CED phosphoramidite consists of a 2′‑deoxyuridine core bearing a 5‑iodo substitution on the uracil base, a 5′‑O‑dimethoxytrityl (DMTr) protecting group, and a 3′‑[(2‑cyanoethyl)-(N,N‑diisopropyl)]‑phosphoramidite moiety for automated DNA synthesis.