Study on the Synthesis of 2,6-di(pyridin-2-yl)pyridin- 4(1H)-one
Shuo Wang
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, P. R. China
Jie Chen
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, P. R. China
Liangchun Li *
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, P. R. China
*Author to whom correspondence should be addressed.
Abstract
In this paper, 2,6-di(pyridin-2-yl)pyridin-4(1H)-one was synthesized from ethyl picolinate and acetone via Kröhnke-type reaction. Initially, optimization of the reaction conditions for the synthesis of 1,5-bis(2′-bipyridyl)pentane-1,3,5-trione 2, such as the molar ratio of ethyl picolinate: acetone: sodium hydride and the reaction temperature, were researched. In the ring-forming step, the different nitrogen sources were also researched. At the end, the optimal reaction conditions obtained: the best reaction temperature of first step is 10°C, the molar ratio of ethyl picolinate: acetone is 2:1.1, and ethyl picolinate: sodium hydride is 2: 3, and the optimum nitrogen source is ammonium formate. Under the optimal reaction conditions, the total yield is obtained up to 66% (the yield is only 37% refer to the literatures).
Keywords: 2,6-di(pyridin-2-yl)pyridin-4(1H)-one, ethyl picolinate, acetone, condensation, cyclization