66154-65-2

Upstream product

• 626-61-9 4-Chloropyridine 
• 536-57-2 p-toluene sulfinic acid 
• 5421-92-1 1-(4-pyridyl)pyridinium chloride hydrochloride 
• 111-34-2 -butyl vinyl ether 
• 824-79-3 sodium 4-methylbenzenesulfinate 
• 504-24-5 4-aminopyridine 
• 15854-87-2 4-iodopyridine 
• 7379-35-3 4-chlorpyridine hydrochloride 

Relevant academic research and scientific papers

Divergent reactivity of sulfinates with pyridinium salts based on one-: Versus two-electron pathways

One of the main goals of modern synthesis is to develop distinct reaction pathways from identical starting materials for the efficient synthesis of diverse compounds. Herein, we disclose the unique divergent reactivity of the combination sets of pyridinium salts and sulfinates to achieve sulfonative pyridylation of alkenes and direct C4-sulfonylation of pyridines by controlling the one- versus two-electron reaction manifolds for the selective formation of each product. Base-catalyzed cross-coupling between sulfinates and N-amidopyridinium salts led to the direct introduction of a sulfonyl group into the C4 position of pyridines. Remarkably, the reactivity of this set of compounds is completely altered upon exposure to visible light: electron donor-acceptor complexes of N-amidopyridinium salts and sulfinates are formed to enable access to sulfonyl radicals. In this catalyst-free radical pathway, both sulfonyl and pyridyl groups could be incorporated into alkenes via a three-component reaction, which provides facile access to a variety of β-pyridyl alkyl sulfones. These two reactions are orthogonal and complementary, achieving a broad substrate scope in a late-stage fashion under mild reaction conditions.

Selective Functionalization of Aminoheterocycles by a Pyrylium Salt

The functionalization of aminoheterocycles by using a pyrylium tetrafluoroborate reagent (Pyry-BF4) is presented. This reagent efficiently condenses with a great variety of heterocyclic amines and primes the C?N bond for nucleophilic aromatic substitution. More than 60 examples for the formation of C?O, C?N, C?S, or C?SO2R bonds are disclosed herein. In contrast to C?N activation through diazotization and polyalkylation, this method is characterized by its mild conditions and impressive functional-group tolerance. In addition to small-molecule derivatization, Pyry-BF4 allows the introduction of functional groups in a late-stage fashion to furnish highly functionalized structures.

Convenient and Inexpensive Route to Sulfonylated Pyridines via S N Ar Reaction of Electron-Rich Pyridines by Iron Catalysis

Sulfonylated pyridines were synthesized in moderate to excellent yields, with a wide scope of substituted pyridines and sulfinate salts as starting materials, by an iron-catalyzed S N Ar reaction. This new methodology exhibits advantages for the synthesis of these useful substrates, such as the use of a readily available, inexpensive catalyst, prevention of the disproportionation of the sulfinate salts, and, more importantly, providing access to electron-rich pyridine substrates.

A practical, one-pot synthesis of sulfonylated pyridines

A concise and efficient one-pot synthesis of functionalized sulfonylated pyridines via an SNAr reaction of readily available pyridines and sodium sulfinate salts in the presence of tetrabutylammonium chloride is presented.