- Mixed metal MgO-ZrO2 nanoparticle-catalyzed O-tert-Boc protection of alcohols and phenols under solvent-free conditions
-
An environmentally benign method for O-tert-Boc protection of alcohols and phenols catalyzed by MgO-ZrO2 nanoparticles under solvent-free conditions is described. A variety of phenols, alcohols (aliphatic and aromatic) were converted to corresponding O-tert-Boc products in good to excellent yield (50-95%). The present protocol is expedient, simple, and efficient under solvent-free conditions. The MgO-ZrO2 Nps are easily prepared from inexpensive precursors, and are reusable, recyclable and chemoselective. Copyright 2012 John Wiley & Sons, Ltd. Copyright
- Gawande, Manoj B.,Shelke, Sharad N.,Branco, Paula S.,Rathi, Anuj,Pandey, Rajesh K.
-
experimental part
p. 395 - 400
(2012/09/25)
-
- Chemoselective O-tert-butoxycarbonylation of phenols using 6,7-dimethoxyisoquinoline as a novel organocatalyst
-
The chemoselective O-tert-butoxycarbonylation of phenols using low levels (5-0.1 mol %) of 6,7-dimeth-oxyisoquinoline as a reusable organocatalyst is described.
- Saito, Yukako,Yoshimura, Yuichi,Takahata, Hiroki
-
experimental part
p. 6915 - 6917
(2011/03/18)
-
- Triphenylphosphine as a novel organocatalyst for chemoselective O-tert-butoxycarbonylation of phenols
-
A novel organocatalytic procedure for the chemoselective O-tert-butoxycarbonylation of phenols under neutral and neat conditions is described. Georg Thieme Verlag Stuttgart.
- Chebolu, Rajesh,Chankeshwara, Sunay V.,Chakraborti, Asit K.
-
p. 1448 - 1454
(2008/12/21)
-
- Organocatalytic methods for chemoselective O-tert-butoxycarbonylation of phenols and their regeneration from the O-t-Boc derivatives
-
(Chemical Equation Presented) Carbon tetrabromide (CBr4) catalyzes O-tert-butoxycarbonylation of functionalized phenols without any side reactions (bromination, addition of CBr3 to a double bond, and formation of symmetrical diaryl carbonates, cyclic carbonates, or carbonic-carbonic anhydrides). The parent phenols are regenerated from the O-t-Boc derivatives by the catalyst system CBr4-PPh3 without affecting other protecting groups (aryl alkyl ether, alkyl ester, and thioacetal) or competitive side reaction such as bromination, nitrene (from NO2) and α,α-dibromoolefine (with CHO/COMe) formation, and transesterification (with CO2Me/Et) taking place.
- Chankeshwara, Sunay V.,Chebolu, Rajesh,Chakraborti, Asit K.
-
supporting information; scheme or table
p. 8615 - 8618
(2009/04/11)
-