in this investigation, nano silica chloride (nano sio2cl) has been found to be efficient, chemoselective and recyclable catalyst for facile and simple synthesis of germinal diacetates from aromatic and heteroaromatic aldehydes in shorter reaction durations. the products were obtained in high to excellent yields. this work consistently has the advantages of excellent yields, short reaction time,...

UNLABELLED BACKGROUND Structurally diverse aldehydes are successfully converted into acylals (1,1-diacetates) with acetic anhydride using NaHSO4-SiO2 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 al...

A novel heterogeneous efficient procedure has been developed for the chemoselective synthesis of acylals (1,1-diacetates) under solvent-free conditions. A novel catalyst prepared by the sulfuric acid catalyzed copolymerization of p-toluenesulfonic acid and paraformaldehyde displays extremely high activities for the title reactions, affording average yields over 90% within several minutes. A com...

2.7. Redox Deprotections 221 3. Thiol Protecting Groups 223 4. Carboxy Protecting Groups 223 4.1. Protection 224 4.2. Deprotection 226 5. Carbonyl Protecting Groups 227 5.1. Acetals 227 5.1.1. Protection 227 5.1.2. Deprotection 231 5.2. Dithioacetals 233 5.2.1. Protection 233 5.2.2. Deprotection 235 5.3. 1,3-Oxathiolanes 237 5.4. 1,1-Diacetates (Acylals) 238 5.4.1. Protection 238 5.4.2. Deprote...

4-dodecylbenzenesulfonic acid (dbsa) has been shown to be an efficient, mild, green, stable and chemoselective brønsted acid catalyst for the synthesis of 1, 1-diacetates (acylals) of aldehydes under solvent-free conditions. the mild condition, eco-friendly, excellent yields, short reaction times and using an easily available, inexpensive and reusable catalyst are important features of this met...