438457-58-0

Upstream product

• 18162-48-6 tert-butyldimethylsilyl chloride 
• 123-08-0 4-hydroxy-benzaldehyde 
• 108-24-7 acetic anhydride 
• 120743-99-9 p-[(tert-butyldimethylsilyl)oxy]benzaldehyde 

Downstream Products

• 120743-99-9 p-[(tert-butyldimethylsilyl)oxy]benzaldehyde 

Relevant academic research and scientific papers

Mild and chemoselective synthesis and deprotection of geminal diacetates catalyzed by titanium(IV) halides

A novel, mild, and chemoselective method was developed for the preparation of gem-diacetates from aldehydes and acetic anhydride in the presence of titanium(IV) fluoride (1-5 mol%) under solvent-free conditions at room temperature. The reaction showed a high chemoselectivity toward aldehydes in the presence of ketones. Moreover, titanium(IV) fluoride also catalyzed the deprotection of gem-diacetates to the corresponding aldehydes in water. This efficient and simple method has several benefits, including the use of an inexpensive catalyst, solvent-free conditions, mild reaction temperatures, and high yields, which make it both cost-effective and environmentally friendly. Georg Thieme Verlag Stuttgart.

Silica phosphoric acid: An efficient and recyclable catalyst for the solvent-free synthesis of acylals and their deprotection in MeOH

Silica phosphoric acid was used as an efficient, mild, and recyclable solid catalyst for the synthesis of acylals from various structurally diverse aldehydes and acetic anhydride under solvent-free conditions. The acylation of aldehydes was highly chemoselective, and no ketone was acylated, which provided a method for the synthesis of acylals from aldehydes in the presence of ketones. Silica phosphoric acid-catalyzed deprotection of acylals to the corresponding aldehydes in MeOH has also been developed with excellent yield. The deprotection of the acylals of aromatic aldehydes took priority over those of aliphatic aldehydes. Copyright Taylor & Francis Group, LLC.

Mild and efficient chemoselective synthesis of acetals and geminal diacetates (acylals) from aldehydes using lanthanum(III) nitrate hexahydrate

A mild and efficient chemoselective method has been developed for the preparation of acetals and gem-diacetates in good to excellent yields through a reaction of aldehydes with ethlyleneglycol or acetic anhydride using catalytic amounts of lanthanum(III) nitrate hexahydrate as a catalyst under solvent-free conditions. Copyright Taylor & Francis Group, LLC.

A facile and efficient conversion of aldehydes into 1,1-diacetates (acylals) using iron(III) fluoride as a novel catalyst

Aldehydes are smoothly converted into the corresponding 1,1-diacetates (acylals) in high yields in the presence of a catalytic amount (0.1 mol-%) of iron(III) fluoride at room temperature. The noteworthy features of the present system are shorter reaction times, chemoselective protection of aldehydes, and solvent-free conditions. The procedure is especially useful for large-scale syntheses as the catalyst is highly effective from the view of activity, selectivity, reusability, and economy in the preparation of 1,1-diacetates (acylals). CSIRO 2007.

A versatile and practical synthesis of 1,1-diacetates from aldehydes catalyzed by cyanuric chloride

Structurally diverse aldehydes are successfully converted into 1,1-diacetates with acetic anhydride using cyanuric chloride as a mild, convenient and inexpensive catalyst under solvent-free conditions. The noteworthy features of the present system are shorter reaction times, and mild and solvent-free conditions. Furthermore, it offers chemoselective protection of aldehydes.

A remarkable HBF4-SiO2-catalyzed synthesis of acylals from aldehydes under solvent-free conditions

HBF4-SiO2 has been found to be an outstanding catalyst for the protection of carbonyl compounds as acylals under entirely solvent-free conditions. Some of the major advantages of this procedure are high yields, ease of operation, high chemoselectivity, high atom efficiency, and compatibility with other protecting groups. Georg Thieme Verlag Stuttgart.

An efficient method for the synthesis of acylals from aldehydes using silica-supported perchloric acid (HClO4-SiO2)

The synthesis of acylals from structurally diverse aldehydes has been performed in excellent yields under solvent-free conditions using HClO4-SiO2 as a mild, convenient, reusable, and heterogeneous catalyst. The procedure is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the catalyst can be recovered simply and reused efficiently a number of times without appreciable loss of activity.

Lithium chloride-assisted chemoselective conversion of aldehydes into geminal diacetates under solvent-free conditions

A mixture of lithium chloride and acetic anhydride was used for converting aldehydes into geminal diacetates under solvent-free conditions in high yields. Copyright Taylor & Francis, Inc.

Reinvestigation of the mechanism of gem-diacylation: Chemoselective conversion of aldehydes to various gem-diacylates and their cleavage under acidic and basic conditions

The mechanism of gem-diacylate formation has been studied extensively using tetrabutylammonium tribromide (TBATB) as the catalyst. The reaction proceeds by a nucleophilic attack of an anhydride on an aldehydic carbonyl group, nucleophilic attack of the hemiacylate intermediate on a second molecule of the anhydride, followed by an intermolecular attack of a second acetate group to regenerate the anhydride. gem-Diacylates of various aliphatic and aromatic aldehydes were obtained directly from the reaction of a variety of aliphatic and aromatic acid anhydrides in the presence of a catalytic quantity of tetrabutylammonium tribromide (TBATB) under solvent-free conditions. A significant electronic effect was observed during its formation as well as deprotection to the corresponding aldehyde. Chemoselective gem-diacylation of the aromatic aldehyde containing an electron-donating group has been achieved in the presence of an aldehyde containing an electron-withdrawing group. Deprotection of the gem-diacylate to the parent carbonyl compound can be accomplished in methanol in presence of the same catalyst. Here again, chemoselective deprotection of the gem-diacylate of a substrate containing an electron-donating group has been achieved in the presence of a substrate containing an electron-withdrawing group. Both the acid and base stability order of the various gem-diacylates examined follow a similar order. The stability order determined from the present study is: gem-dibenzoate > gem-dipivalate > gem-diisobutyrate > gem-diacetate > gem-dipropionate. All the gem-diacylals are more stable under basic conditions than acidic condition. No correlation was found between the stability order and the pKa's of the corresponding acids; rather, the stability order is directly related to the steric crowding around the carbonyl carbon. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.

Bismuth compounds in organic synthesis. Bismuth nitrate catalyzed chemoselective synthesis of acylals from aromatic aldehydes

Aromatic aldehydes are smoothly converted into the corresponding acylals in good yields in the presence of 3-10mol% Bi(NO3) 3·5H2O. Ketones are not affected under the reaction conditions. The relatively non-toxic nature of the catalyst, its ease of handling, easy availability and low cost make this procedure especially attractive for large-scale synthesis.