Synthesis of Pyran Fragments 1 and 2

A rapid and environmentally friendly method is developed for the synthesis of a series of new substituted 2-amino-4H-pyran-3-carbonitriles through a one-pot condensation of malononitrile and α, α′-bis(arylidene) cycloalkanones in ethanol by using K2CO3 as a catalyst. Short experimental reaction times, excellent yields, no need to use cumbersome apparatus for purification of the products, and inexpensiveness and commercially availability of the catalyst are the advantages of this method.

Synthesis of (2R)-(+)-2,3-Dihydro-2,6-dimethyl-4H-pyran …

(2006) Convergent and Diastereoselective Synthesis of the Polycyclic Pyran Core of Saudin.

Methods for the synthesis of pyran ring.

The natural product saudin was found to induce hypoglycemia in mice and, therefore, could be an appealing lead structure for the development of new agents to treat diabetes. A diastereoselective tandem Stilleoxa- electrocyclization reaction has been developed which provides access to the core structure of saudin in a rapid and convergent manner. This new reaction has been extended to the convergent preparation of a series of polycyclic pyran systems. Progress has been made on the advancement of these complex pyran systems toward the natural product. A complete account of these synthetic efforts is presented.

Categories: Synthesis of O-Heterocycles > Synthesis of 4H-pyrans

N2 - The natural product saudin was found to induce hypoglycemia in mice and, therefore, could be an appealing lead structure for the development of new agents to treat diabetes. A diastereoselective tandem Stilleoxa- electrocyclization reaction has been developed which provides access to the core structure of saudin in a rapid and convergent manner. This new reaction has been extended to the convergent preparation of a series of polycyclic pyran systems. Progress has been made on the advancement of these complex pyran systems toward the natural product. A complete account of these synthetic efforts is presented.


Thieme E-Books & E-Journals - Synthesis / Issue

In continuation of our studies on the development of inexpensive and environmentally benign methodologies for organic reactions [–], herein we report a highly versatile and efficient synthesis of 2-amino-4H-pyran-3-carbonitriles 3a–q () from α, α′-bis(Arylidene) cycloalkanone 1, malononitrile 2 and catalytic amounts of K2CO3. In a typical reaction, a mixture of 1 and 2 (1:1) equivalents, respectively, and K2CO3 (cat.) was refluxed in ethanol for 5–60min. The results are summarized in ().

One-Pot Multicomponent Solvent-Free Synthesis of 2 …

In order to show the merits of K2CO3 over other catalysts reported in the literature, results for the synthesis of 2-amino-4H-pyran-3-carbonitriles obtained using K2CO3 as the catalyst were compared with those obtained using other catalysts. clearly shows that K2CO3 appears to promote the reaction more effectively than a number of other catalysts, particularly in terms of the time and yield required to complete the reaction.

Pyridine synthesis - Organic chemistry

In conclusion, the present method is a simple and environmentally friendly procedure for the synthesis of a series of new 2-amino-4H-pyran-3-carbonitriles using catalytic amount of K2CO3. The simple experimental procedure, short reaction times, excellent yields of products, mild reaction condition, easy purification, economic availability of the catalyst, and green standard are the advantages of this method.