A Green Protocol for Chemoselective O‐Acylation in the Presence of Zinc Oxide as a Heterogeneous, Reusable and Eco‐Friendly Catalyst.

Abstract

Protection O 0345 A Green Protocol for Chemoselective O-Acylation in the Presence of Zinc Oxide as a Heterogeneous, Reusable and Eco-Friendly Catalyst. -A series of 14 alcohols and 3 phenols is acylated efficiently under mild and solvent-free conditions using zinc oxide as a cheap and reusable catalyst. Competing experiments show that alcohols are acylated selectively in the presence of phenols and primary alcohols in the presence of secondary ones. -(TAMADDON*, F.; AMROLLAHI, M. A.; SHARAFAT, L.; Tetrahedron Lett. 46 (2005) 45, 7841-7844; Dep. Chem., Coll. Sci., Yazd Univ., Yazd 89195, Iran; Eng.) -Roy 07-057

Synthesis and Characterization of Water Soluble Rosin-Polyethylene Glycol 1500 Derivative

“…Zinc oxide showed the most effective catalyst as it resulted in the highest conversion of ester at 5 hours due to lewis acid performance of this catalyst however zinc dust did not, it may suggest that zinc cation is more readily dissolved from oxide surface into the reaction media comparing with metallic Zn [9]. Even though zinc oxide and tin chloride are lewis acid but zinc oxide showed higher reaction rate than tin chloride due to moisture and temperature stable of zinc oxide and the result showed consistence with previous studied [10], [11]. Therefore zinc oxide was selected for esterification reaction.…”

Nano-ZnO Catalyzed Multicomponent One-Pot Synthesis of Novel Spiro(indoline-pyranodioxine) Derivatives

“…The recent literature survey reveals that nano-ZnO as heterogeneous catalyst has received considerable attention because of its ecofriendly nature and has been explored as a powerful catalyst for several organic transformations [17][18][19][20][21][22]. To the best of our knowledge, there is no report available in the literature regarding the reaction of 1Hindol-2,3-diones and activated methylene reagent (malononitrile/ethylcyanoacetate) with 2,2-dimethyl-1,3-dioxane-4,6diones.…”

Greener Solvent-Free Reactions on ZnO

“…Also, the amino group in aminophenol was selectivity acylated (Scheme 3). Similarly, in another studies, O-acylation of alcohols and phenols with acid chlorides were performed employing ZnO and nano ZnO, (Moghaddam & Saeidian 2007;Tammaddon et al, 2005;Tayebee et al, 2010).…”