Niobium-Catalyzed Intramolecular Addition of O–H and N–H Bonds to Alkenes: A Tool for Hydrofunctionalization

Abstract

A convenient, versatile and easy to handle intramolecular hydrofunctionalization of alkenes (C-O and C-N bonds formation) is reported using a novel niobium-based catalytic system. This atom economic and eco-friendly methodology provides an additional synthetic tool for the straightforward formation of valuable building blocks enabling molecular complexity. Various pyran, furan, pyrrolidine, piperidine, lactone, lactam derivatives as well as spirocyclic compounds are produced in high yields and selectivities.

Desaturation via Redox-Neutral Hydrogen Transfer Process: Synthesis of 2-Allyl Anilines, Mechanism and Applications

“…and aqueous NaHCO3 (20 mL) in sequence, and the organic phase was dried over MgSO4, and the solvent was evaporated under vacuum after filtration. The resulting residues was purified by column chromatography on silica gel with hexanes/ethyl acetate (10:1 to 5:1) as the eluent to give the desired product 12 in 80% yield, 30.4 mg. 6, 142.9, 141.6, 137.4, 129.4, 128.7, 128.5, 127.9, 126.9, 126.3, 124.9, 123.3, 113.7, 76.4, 66.5, 44.2, 21.6 Procedure for the preparation of 13 (Ferrand et al, 2017).…”

Earth-Abundant 3d Transition Metal Catalysts for Hydroalkoxylation and Hydroamination of Unactivated Alkenes

“…onto unactivated olefins will also be covered but the term hydroamidation will be preferred to refer to these compounds bearing electronwithdrawing substituents. The O-H bond formation reactions by hydration [35,36] or hydroacyloxylation [37][38][39] of unactivated alkenes are not included in this survey. The achievements are summarized according to the nature of the 3d transition metal and the type of hydrofunctionalization reaction.…”

Bisphosphonium salt: an effective photocatalyst for the intramolecular hydroalkoxylation of olefins

“…Saturated cyclic ethers are important structural scaffolds found in many biologically active natural products, pharmaceuticals and agrochemicals [19]. One of the most straightforward and attractive synthetic strategies for constructing these cyclic ether motifs is the catalytic intramolecular hydroalkoxylation of alkenes enabled by transition metals or Lewis acids, generally delivering Markovnikov-type addition products [20,[21][22][23][24][25][26][27][28][29][30][31][32][33]. Recently, Nicewicz and coworkers reported a catalytic intramolecular anti-Markovnikov hydroalkoxylation of alkenes via visible light photoredox catalysis [34][35][36].…”