Acetylation of unsymmetrical diols in the presence of Al2O3

Mild and Highly Efficient Copper(I) Inspired Acylation of Alcohols and Polyols

“…Some notable methods include the use of I 2 [2][3][4], Br 2 [5] montmorillonite K-10 [6], FeCl 3 [7], TiCl 4 -AgClO 4 [8], LiClO 4 [9], CuSO 4 ·5H 2 O [10], TMSOTf [11], Bu 3 P in CH 2 Cl 2 [12,13], La(NO 3 ) 3 ·6H 2 O [14], HClO 4 -SiO 2 [15], molecular sieves [16], NaHCO 3 [17], Mg(NTf 2 ) 2 [18], 3-nitrobenzeneboronic acid [19], alumina [20], NBS [21], TaCl 5 [22], VO(OAc) 2 [23] and metal triflates such as Pd(PhCN) 2 (OTf) [24], Cu(OTf) 2 [25], Bi(OTf) 2 [26], In(OTf) 2 [27,28], Sc(OTf) 2 [29], Ce(OTf) 2 [30], and CoCl 2 [31,32].…”

Acetylation of Alcohols, Amines, Phenols, Thiols under Catalyst and Solvent-Free Conditions

“…Acetylation is one of the most important reactions in organic synthesis because acetyl groups can be conveniently used to protect a wide range of functional groups including alcohols, amines, phenols, and thiols, among others [1,2]. Acetylation with acyl halides or acid anhydrides has been reported using either homogeneous or heterogeneous acid catalysts [3][4][5][6][7][8][9][10][11][12] or base catalysts [13][14][15][16][17]. Subsequently, a wide range of homogeneous transition-metal-based or organocatalysts have been developed for the acetylation of alcohols using RuCl 3 [18], CeCl 3 [19], ZrCl 4 [20], La(NO 3 )•6H 2 O [21], Al(OTf) 3 [22], AgOTf [23], Co(II)salen-complex [24], NiCl 2 [25], CoCl 2 [26], iodine [27], Ph 3 P + CH 2 COMeBr − [28], Cp 2 ZrCl 2 [29], Mg(NTf 2 ) 2 [30], H 3 [P(Mo 3 O 10 ) 4 ]•nH 2 O [31], 3-nitrobenzeneboronic acid [32], (4-dimethylaminopyridine) [33], (4-(N,N -dimethylamino)pyridine hydrochloride) [34], CuZr(PO 4 ) 2 NPs [35], melamine trisulfonic acid [36], tin(IV)porphyrin-hexamolybdate [37], and NaOAc•3H 2 O [38].…”

Highly Efficient Cationic Palladium Catalyzed Acetylation of Alcohols and Carbohydrate-Derived Polyols

“…Some notable examples include the use of tributylphosphine [6,7], bromine [8], p-Toluenesulfonic acid [9], alumina [10], scandium triflate [11], indium triflate [12,13], bismuth triflate [14], trimethylsilyl triflate [15], copper triflate [16], cerium triflate [17], ruthenium chloride [18], sulfamic acid [19], montmorillonite K-10 [20], molecular sieves [21], iron (III)chloride [22], magnesium bromide [23], tantalum chloride [24], vanadyl acetate [25], N-bromosuccinamide (NBS) [26], 3-nitrobenzeneboronic acid [27], lithium perchlorate (LiClO 4 ) [28], silica gel supported sodium hydrogen sulfate [29], sodium acetate trihydrate [1], dried sodium bicarbonate [30] and Iodine [31,32]. While these methods provides viable alternative for acetylating alcohols, some of these methods utilizes catalysts that are expensive, moisture sensitive, require long reaction times and tedious work-up protocols and sometimes result in low yields.…”