Selective Monobenzoylation of 1,2- and 1,3-Diols Catalyzed by Me₂SnCl₂ in Water (Organic Solvent Free) under Mild Conditions

Abstract

We have developed an efficient method for selective monobenzoylation of 1,2- and 1,3-diols in water catalyzed by Me(2)SnCl(2). Treatment of 1,2- and 1,3-diols with benzoyl chlorides, DMT-MM, and potassium carbonate in the presence of a catalytic amount of Me(2)SnCl(2) and DMAP in water at room temperature gave monobenzoates in up to 97% yield.

DBN‐Catalyzed Regioselective Acylation of Carbohydrates and Diols in Ethyl Acetate

“…[1][2][3][4][5][6][7][8][9][10][11] Regioselective acylation is of great importance in the synthesis of valuable oligosaccharide structural units because it facilitates the protection and deprotection of hydroxyl groups and the synthesis of target building blocks. [12][13][14][15][16][17][18] Recently, many methods have been developed to make regioselective acylations highly efficient, green, and even controllable, and some metal catalysts and organic small molecules have been used for the regioselective acylation of carbohydrates and diols; for example, tin(IV), [19][20][21] boron(IV), [22] copper(II), [23][24][25] silver(I), [26] and iron catalysts have been recently reported. [27,28] Organotin reagents are the most widely used reagents for the selective protection of carbohydrates because over the years, they have been developed into easy to handle and generally highly regioselective reagents for the derivatization of diols and polyols.…”

A New Lavandulol-related Monoterpene in the Sex Pheromone of the Grey Pineapple Mealybug, Dysmicoccus neobrevipes

“…(Ho et al 2007) Planococcus kraunhiae (Sugie et al 2008) Planococcus ficus (Hinkens et al 2001) Maconellicoccus hirsutus (Zhang et al 2004) Thus, mealybugs may have a common biosynthetic mechanism to connect isoprene units in a different manner from general monoterpene biosynthesis in other organisms. We started the synthesis of compound (4) from a symmetric dicarboxylic ester, diethyl isopropylmalonate, which was reduced to a 1,3-diol (1) and mono-acetylated to monohydroxyacetate (2) using dimethyltin(IV) dichloride as a catalyst (Muramatsu et al 2012). This was oxidized using AZADO as a catalyst (Shibuya et al 2006) to give an acetate with a formyl group (3) that was coupled with 2-methyl-2-propenyltriphenylphosphonium bromide in a Wittig reaction.…”

Catalyst Free Selective Monobenzoylation of Diols with Benzoyl Cyanide: A Robust and Regioselective Strategy

“…The present protocol is simple to handle and does not involve any catalyst detrimental to environmental safety. While as the general methods developed in earlier studies though efficient, but they also require the use of toxic metal‐based catalysts as reported in Scheme …”

“…As a result, regio-and stereoselective functionalization of non-protected polyols like carbohydrates, inositols and highly functionalized natural products with nonenzymatic catalysts have been a formidable challenge. Though many protocols for selective protection of hydroxyl groups have emerged in literature [1][2] but procedures that display high levels of substrate generality are still limited barring a few metal catalyzed methods [3][4][5][6] (Scheme 1). Over the years, the protection methods that have been developed include the use of catalysts such as organotin, [7][8][9] organoboron, [10][11] organosilicon, [12][13][14] metal salts, [15][16][17][18][19][20] organobases [21][22][23][24] and enzymes.…”