Preparation and characterization of BF3 supported on coconut shell as a novel and effective nano-catalyst for one-pot synthesis of pyrano[2,3-d]pyrimidines

Abstract

In this paper, boron trifluoride supported on coconut shell nano-particles (nano-BF 2 O-coc) was prepared from nano-crystalline coconut shell through mechanical method using ultrasonication. The resultant was utilized to obtain nano-crystalline BF 3 supported on coconut shell nano-particles (nano-BF 2 O-coc). The novel nanostructure has been characterized using Fourier transform infrared spectroscopy, transmission electron microscopy, field-emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDX) techniques. The catalytic activity of the solid acid catalyst has been successfully examined in a one-pot, three-component condensation reaction of barbituric acid, ethyl cyanoacetate or malononitrile, and aldehydes in refluxing ethanol to furnish pyrano[2,3-d]pyrimidine derivatives.

Recent progress of nanocatalyst in the synthesis of heterocyclic compounds by barbituric acids

“…This method opens a new window for forming new nanocatalysts from plants and fruits comprising cellulose. 99 BF 3 efficiently completed the preparation of coc-BF 2 O-nano to Coconut-OH. First, the outer brown shell of the coconut was rinsed repetitively with water and then put into an ice/H 2 O bath (Ultrasonicator).…”

“…Next, BF 3 was added drop by drop at 0 C to the suspension of nano-coconut and stirred for 2 h to eliminate HF and produce Coconut-OBF 2 nanocatalyst. 99 Coconut…”

“…Finally, after tautomerization conversion, cyclization and 1,3-proton exchange generated the relevant compound 4 or 76. 99…”

“…Lower reaction period, green starting materials made from plants and fruits, eco‐friendly reaction, high yields, and reusability for several successive cycles without any considerable loss of properties, and filtering and purifying the formed materials just by simple crystallization are the most impressive features of this present protocol. This method opens a new window for forming new nanocatalysts from plants and fruits comprising cellulose 99 …”

Importance of Hybrid Catalysts toward the Synthesis of 5H-Pyrano[2,3-d]pyrimidine-2-ones/2,4-diones (Thiones)

“…In addition, in both reactions comparatively similar yield were gained with almost similar time interval. Then Molaei and Sadeghi 99 used nano-BF 2 O-coconut shell as catalyst and attained 59 ’s analogues. Using the same substrate scope as shown in Scheme 45 .…”