127943-91-3Relevant articles and documents
Synthesis of tetrahydropyridine derivatives through a modular assembly reaction using 3,4-dihydropyran as dual substrate and template
Sun, Shaohuan,Cheng, Cheng,Yang, Jian,Taheri, Amir,Jiang, Dan,Zhang, Biao,Gu, Yanlong
, p. 4520 - 4523 (2014)
A concise method to synthesize 1,2,3,4-tetrahydropyridines is described that involves the use of 2-alkoxy-3,4-dihydropyran as a modular precursor to react with aniline and a nucleophile. In this method, the heteroatom of the dihydropyran ring was replaced by nitrogen of aniline while the nucleophile attached to its adjacent position. Various druglike polyheterocycles were prepared with this method by using NH2-containing 1,5- or 1,4-bisnucleophiles.
Diels-Alder Reactions of 1-Alkoxy-1-amino-1,3-butadienes: Direct Synthesis of 6-Substituted and 6,6-Disubstituted 2-Cyclohexenones and 6-Substituted 5,6-Dihydropyran-2-ones
Elkin, Pavel K.,Durfee, Nathaniel D.,Rawal, Viresh H.
supporting information, p. 5288 - 5293 (2021/06/30)
We report the cycloaddition reactions of 1-alkoxy-1-amino-1,3-butadienes. These doubly activated dienes are prepared on a multigram scale from crotonic acid chloride and its derivatives. The dienes undergo Diels-Alder (DA) and hetero-Diels-Alder (HDA) reactions under mild reaction conditions with a variety of electron-deficient dienophiles to afford cycloadducts in good yields with excellent regioselectivities. The hydrolysis of the DA cycloadducts provides 6-substituted and 6,6-disubstituted 2-cylohexenones, which are versatile building blocks for complex molecule synthesis. The corresponding HDA cycloadducts afford 6-substituted 5,6-dihydropyran-2-ones.
Hollow Hyper-Cross-Linked Nanospheres with Acid and Base Sites as Efficient and Water-Stable Catalysts for One-Pot Tandem Reactions
Jia, Zhifang,Wang, Kewei,Tan, Bien,Gu, Yanlong
, p. 3693 - 3702 (2017/06/09)
A task-specific functionalized hyper-cross-linked polymer (HCP) with hollow spherical structure was synthesized by an easily accessible Friedel-Crafts reaction-based approach. A harmonious coexistence of acid (sulfonic acid) and base (amine) sites on a microporous organic material was achieved. The acid-base bifunctional HCP catalyst (HCP-A-B) structure was fully characterized by many physicochemical methods. In the subsequent tandem reactions (hydrolysis/Henry and hydrolysis/Knoevenagel reactions), the HCP-A-B catalyst displayed high catalytic efficiency and chemical stability toward water or organic solvent. These HCP-A-B catalyst characteristics led to the development of a previously unreported transformation of 2-ethoxy-3,4-dihydropyran derivative to a 2-cyclohexen-1-one derivative through a tandem reaction involving water-assisted ring-opening hydrolysis of the dihydropyran, an intramolecular aldol reaction, and a dehydration reaction. In all of these reactions, the bifunctional HCP-A-B catalyst can be recovered and reused more than 10 times without significant loss of activity.