55169-75-0

Upstream product

• 110-86-1 pyridine 
• 98-88-4 benzoyl chloride 
• 18031-56-6 methyl-[O⁴,O⁶-((R)-benzylidene)-O³-trifluoroacetyl-α-D-glucopyranoside] 
• 67-56-1 methanol 
• 389-04-8 methyl-[O²-benzoyl-O⁴,O⁶-((R)-benzylidene)-O³-trifluoroacetyl-α-D-glucopyranoside] 
• 64-17-5 ethanol 
• 54769-36-7 N-benzoyloxybenzotriazole 
• 3162-96-7 4,6-O-benzylidene-1-O-methyl-α-D-glucopyranoside 
• 93-97-0 benzoic acid anhydride 
• 65-85-0 benzoic acid 
• 1202384-88-0 C₂₃H₂₄O₉ 
• 2641-79-4 methyl 2,3,4,6-tetrakis-O-trimethylsilyl-α-D-glucopyranoside 
• 108-24-7 acetic anhydride 
• 100-52-7 benzaldehyde 

Downstream Products

• 118246-03-0 methyl 2,3,4-tri-O-acetyl-O-α-L-rhamnopyranosyI-(1->3)-2-O-benzoyl-4,6-O-benzylidene-O-α-D-gluco-pyranoside 
• 21056-53-1 methyl O²-benzoyl-α-D-glucoside 
• 221002-70-6 methyl 2‐O‐benzoyl‐3‐O‐benzyl‐4,6‐O-benzylidene‐α‐D‐glucopyranoside 
• 383422-35-3 Benzoic acid (2R,4aR,6S,7R,8S,8aR)-8-{(2S,3R,4S,5R,6R)-3-[2-(2-allyloxy-phenyl)-acetoxy]-4,5-bis-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-2-yloxy}-6-methoxy-2-phenyl-hexahydro-pyrano[3,2-d][1,3]dioxin-7-yl ester 
• 593281-67-5 methyl (2,4,6-tri-O-acetyl-3-azido-3-deoxy-β-D-glucopyranosyl)-(1->3)-2-O-benzoyl-4,6-O-benzylidene-α-D-glucopyranoside 
• 365418-32-2 Benzoic acid (2R,4aR,6S,7R,8S,8aR)-6-methoxy-8-phenoxythiocarbonyloxy-2-phenyl-hexahydro-pyrano[3,2-d][1,3]dioxin-7-yl ester 
• 130052-73-2 methyl O-(tetra-O-acetyl-β-D-glucopyranosyl)-(1->3)-O-(tri-O-acetyl-β-D-glucopyranosyl)-(1->3)-2-O-benzoyl-4,6-O-benzylidene-α-D-glucoside 
• 99745-48-9 Methyl-3-amino-4,6-O-benzyliden-3-desoxy-α-D-allopyranosid 
• 99679-92-2 Methyl-3-<(benzyloxycarbonyl)amino>-3,4-didesoxy-α-D-glycero-hex-3-enopyranosid-2-ulose 
• 99679-82-0 ((2R,4aR,6S,7R,8S,8aS)-7-Hydroxy-6-methoxy-2-phenyl-hexahydro-pyrano[3,2-d][1,3]dioxin-8-yl)-carbamic acid methyl ester 
• 99679-81-9 Methyl-4,6-O-benzyliden-3-desoxy-3-<(methoxycarbonyl)amino>-α-D-ribo-hexopyranosid-2-ulose 
• 99679-90-0 Methyl-4,6-O-benzyliden-3-<(benzyloxycarbonyl)amino>-3-desoxy-3-C-methyl-α-D-arabino-hexopyranosid-2-ulose 
• 99679-91-1 Methyl-4,6-O-benzyliden-3-<(benzyloxycarbonyl)amino>-2-O-methyl-3-desoxy-α-D-erythro-hex-2-enopyranosid 
• 99745-49-0 Methyl-4,6-O-benzyliden-3-<(benzyloxycarbonyl)amino>-3-desoxy-α-D-allopyranosid 

Relevant academic research and scientific papers

Stannous chloride as a low toxicity and extremely cheap catalyst for regio-/site-selective acylation with unusually broad substrate scope

This work reports stannous chloride (SnCl2)-catalyzed regio-/site-selective acylation with unusually broad substrate scope. In addition to 1,2- and 1,3-diols and glycosides containing cis-vicinal diol, the substrate scope also includes glycosides without cis-vicinal diol. For such a substrate scope, usually, only methods using stoichiometric amounts of organotin reagents can lead to the same protection pattern with high selectivities and highly isolated yields (84-97% in most cases). Therefore, SnCl2, as a low toxicity and extremely cheap reagent, should be the best catalyst for regio-/site-selective acylation compared with any previously reported reagents. This journal is

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

The 1,5-diazabicyclo[4.3.0]non-5-ene (DBN)-catalyzed regioselective acylation of carbohydrates and diols in ethyl acetate has been developed. The hydroxyl groups can be selectively acylated by the corresponding anhydride in EtOAc in the presence of a catalytic amount (as low as 0.1 equiv.) of DBN at room temperature to 40 °C. This method avoids metal catalysts and toxic solvents, which makes it comparatively green and mild, and it uses less organic base compared with other selective acylation methods. Mechanism studies indicated that DBN could catalyze the selective acylation of hydroxyl moieties through a dual H-bonding interaction.

Diisopropylethylamine-triggered, highly efficient, self-catalyzed regioselective acylation of carbohydrates and diols

A diisopropylethylamine (DIPEA)-triggered, self-catalyzed, regioselective acylation of carbohydrates and diols is presented. The hydroxyl groups can be acylated by the corresponding anhydride in MeCN in the presence of a catalytic amount of DIPEA. This method is comparatively green and mild as it uses less organic base compared with other selective acylation methods. Mechanistic studies indicate that DIPEA reacts with the anhydride to form a carboxylate ion, and then the carboxylate ion could catalyze the selective acylation through a dual H-bonding interaction.

Enhanced site-selectivity in acylation reactions with substrate-optimized catalysts on solid supports

A concept for site selective acylation of poly-hydroxylated substrates is presented where polymer-supported catalysts are employed: catalytically active DMAP units were combined with a library of small molecule peptides attached to the solid phase with the goal to identify substrate-optimized catalysts through library screening. For selected examples, we demonstrate how the optimized catalysts can convert “their” substrate with a markedly enhanced site-selectivity, compared to only DMAP. Due to the solid support, product purification is significantly simplified, and the peptidic catalysts can be easily reused in multiple cycles while conserving its efficiency.

Highly Regioselective Monoacylation of Unprotected Glucopyranoside Using Transient Directing-Protecting Groups

The regioselective functionalization of monosaccharides is notoriously achieved using metal catalysis, lengthy synthetic strategies requiring protection/deprotection, various enzymes, or other methods that target cis-diols (and thus cannot be used with glucopyranose derivatives), In this paper, we report a new method using selected boronic acids as temporary protecting groups, and describe its application to the regioselective functionalization of methyl α-d-glucopyranoside, the most difficult monosaccharide to functionalize regioselectively. Generally, reactions of glucopyranosides may lead to a plethora of mono- and polyfunctionalized derivatives, yet our method gave the 3-O-acetylated, 2-O-benzoylated, and 2-O-pivaloylated derivatives of methyl α-d-glucopyranoside as major products. We focused on the use of recyclable and green temporary protecting groups (in a one-pot reaction) and on the modulation of the intramolecular hydrogen-bonding network using selected arylboronic acids. A complete scalable procedure leading to a single regioisomer from unprotected methyl α-d-glucopyranoside is presented.

Highly Efficient Selective Benzylation of Carbohydrates Catalyzed by Iron(III) with Silver Oxide and Bromide Anion as Co-catalysts

A highly efficient, green, and regioselective method for the benzylation of diols and polyols was developed. With the use of Ag2O (0.6 equiv.) and tetrabutylammonium bromide (0.1 equiv.) as co-catalysts, the iron(III)-catalyzed benzylation reaction proceeded to completion at 40 °C within 2–3 h and gave the products in high yields with high regioselectivities. A mechanism involving the principle of enhanced basicity of Ag2O by soft anions was proposed.

Site-Selective Acylations with Tailor-Made Catalysts

The acylation of alcohols catalyzed by N,N-dimethylamino pyridine (DMAP) is, despite its widespread use, sometimes confronted with substrate-specific problems: For example, target compounds with multiple hydroxy groups may show insufficient selectivity for one hydroxyl, and the resulting product mixtures are hardly separable. Here we describe a concept that aims at tailor-made catalysts for the site-specific acylation. To this end, we introduce a catalyst library where each entry is constructed by connecting a variable and readily tuned peptide scaffold with a catalytically active unit based on DMAP. For selected examples, we demonstrate how library screening leads to the identification of optimized catalysts, and the substrates of interest can be converted with a markedly enhanced site-selectivity compared with only DMAP. Furthermore, substrate-optimized catalysts of this type can be used to selectively convert "their" substrate in the presence of structurally similar compounds, an important requisite for reactions with mixtures of substances. Substrate-optimized catalysts: Site- selective acylations were achieved using substrate-optimized catalysts (see scheme) as identified from a library screening. The catalysts are composed of low-molecular-weight peptides that are readily tuned through variation of the amino acid sequence, and one amino acid was connected to DMAP to ensure catalytic activity. These substrate-optimized catalysts were also applied to selectively convert one substrate in the presence of a structurally similar compound.

A green and convenient method for regioselective mono and multiple benzoylation of diols and polyols

An efficient method for regioselective benzoylation of diols and polyols was developed. The benzoylation is catalyzed by only 0.2 equiv of benzoate anion in acetonitrile with the addition of a stoichiometric amount of benzoic anhydride under very mild condition, leading to high yields. Compared with all other methods, this method shows particular advantage in regioselective multiple benzoylation of polyols, and in avoiding the use of any metal-based catalysts and any amine bases, which is more environment-friendly.

Regioselective acylation of diols and triols: The cyanide effect

Central topics of carbohydrate chemistry embrace structural modifications of carbohydrates and oligosaccharide synthesis. Both require regioselectively protected building blocks that are mainly available via indirect multistep procedures. Hence, direct pr

Regioselective Benzoylation of 4,6-O-Benzylidene Acetals of Glycopyranosides in the Presence of Transition Metals

Benzoylation of 4,6-O-benzylidene acetals of glycopyranosides by benzoic anhydride in acetonitrile in the presence of Cu(CF3COO)2 as a promoter gave 2-benzoates for α-D-glucopyranosides and α-D-mannopyranosides and 3-benzoates for β-D-galactopyranosides in good yields with high regioselectivity. Benzoylation of 4,6-O-benzylidene acetals of glycopyranosides of D-galactose and D-mannose by benzoyl chloride in the presence of MoO2(acac)2 as a catalyst in all studied cases led to regioselective 3-substitution.