Oxidative chlorination of 4-pentenols and other functionalized hydrocarbons was written by Bruecher, Oliver;Hartung, Jens. And the article was included in Tetrahedron in 2014.Name: Pyridinehydrochloride This article mentions the following:
Substituted 4-pentenols undergo regio- and stereoselective chlorocyclization, when treated in solutions of di-Me carbonate with chloride, a terminal oxidant, and a buffered proton source. Effective oxidants for liberating chlorine-like reactivity from chloride in the temperature range between 20 and 40 °C are tert-Bu hydroperoxide, activated by a titanium(IV) or a molybdenum(VI) ONO-chelate complex, and potassium monoperoxysulfate from the ternary salt 2KHSO5·KHSO4·K2SO4 (oxone). Substituents in the flexible part of the alkenol direct oxidative chlorocyclization 2,5-trans- and 2,4-cis-selectively. (E)-Configuration at the alkene translates anti-specifically into relative configuration of substituents at the β-chlorohydrin ether entity. A Ph group bound to the terminal alkene carbon alters the inherent 5-exo-specificity for chlorocyclization of terminal 4-pentenols toward 6-endo-selectivity, as exemplified by synthesis of trans-3-chloro-2-phenyltetrahydropyran from (E)-5-phenyl-4-penten-1-ol in up to 74% yield. Competition kinetics show that 5-exo-chlorocyclization of 1-phenyl-4-penten-1-ol occurs at 40 °C 600 times faster than electrophilic aromatic chlorosubstitution of anisole. Prenyl-type alkenols undergo allylic chlorination with an ene-type selectivity, as exemplified in synthesis of a building block for the fragrance component rose oxide from citronellol. In the experiment, the researchers used many compounds, for example, Pyridinehydrochloride (cas: 628-13-7Name: Pyridinehydrochloride).
Pyridinehydrochloride (cas: 628-13-7) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Name: Pyridinehydrochloride