tert-butyl 4-(2-ethoxy-2-oxoethylidene)piperidine-1-carboxylate

tert-Butyl 4-(2-ethoxy-2-oxoethylidene)piperidine-1-carboxylate (CAS 135716-08-4) is a strategically functionalized Boc-protected piperidine derivative engineered for pharmaceutical intermediate synthesis, ligand development, and heterocyclic construction. This molecule integrates a saturated piperidine core—with an acid-labile Boc (tert-butoxycarbonyl) protecting group on the nitrogen atom (N1-position)—and an α,β-unsaturated ethyl ester side chain at the C4 position (exocyclic double bond). The N-Boc protection prevents unwanted N-alkylation during synthetic sequences and can be removed under mild acidic conditions, while the conjugated ester moiety offers versatile reactivity including catalytic hydrogenation (to saturated ester), Michael addition, or hydrolysis to the corresponding acid. Compared to its saturated analogs (e.g., CAS 157688-46-5), this unsaturated precursor provides a strategic handle for introducing diversity at the C4 position via conjugate addition or reduction. This intermediate is particularly valuable for constructing CNS-active pharmaceuticals, GPCR ligands, peptidomimetics, and piperidine-based scaffolds where controlled nitrogen reactivity and C4-functionalization are critical. Manufactured with purity ≥98% under controlled conditions, it supports drug discovery programs requiring modular access to differentially protected piperidine architectures with tunable side-chain reactivity.

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Product Name	tert-Butyl 4-(2-ethoxy-2-oxoethylidene)piperidine-1-carboxylate
CAS Number	135716-08-4
Chinese Name	叔丁基 4-(2-乙氧基 -2-氧代亚乙基) 哌啶 -1-羧酸酯
Synonyms	Ethyl (1-Boc-piperidin-4-ylidene)acetate; 1-Boc-4-(ethoxycarbonylmethylene)piperidine; C₁₄H₂₃NO₄ protected unsaturated ester
Chinese Synonyms	1-Boc-4-(乙氧羰基亚甲基) 哌啶; 乙基 (1-Boc-哌啶 -4-亚基) 乙酸酯; Boc-哌啶不饱和酯; 保护性哌啶中间体
Molecular Formula	C₁₄H₂₃NO₄
Molecular Weight	269.34 g/mol
Purity	≥ 98% (HPLC area normalization)
Product Category	Pharmaceutical Intermediates / Piperidine Derivatives / Protected Unsaturated Esters
Appearance	White to off-white crystalline powder
Boiling Point	~280-290°C at 760 mmHg (estimated)
Storage Conditions	Store in a cool, dry, well-ventilated area away from light and moisture. Keep container tightly closed under inert atmosphere (nitrogen). Protect from strong acids to avoid premature Boc deprotection and from strong oxidizing agents.
Shelf Life	24 months under recommended storage conditions
Packaging	100mg/vial, 500mg/vial, 1g/bottle, 5g/bottle, or customized according to customer requirements
Applications	CNS drug synthesis (GPCR ligands), peptidomimetic development, piperidine-based ligand construction, catalytic hydrogenation (to saturated ester), Michael addition reactions, heterocyclic library synthesis
Reactivity	Suitable for selective Boc deprotection (TFA/HCl), ester hydrolysis (to acid), catalytic hydrogenation (to saturated ethyl ester), Michael addition (conjugate addition), and sequential functionalization
Special Note	✅ Unsaturated Ester Scaffold—exocyclic double bond enables hydrogenation or Michael addition. N-Boc enables orthogonal protection. Distinct from saturated analogs (CAS 157688-46-5) by unsaturation. Part of our protected piperidine building block series.