Stereospecific Synthesis ofsec- andtert-Alkyl Azides from Alcohols and Trimethylsilyl Azide by a New Type of Oxidation–Reduction Condensation Using Phenyl Diphenylphosphinite and Trimethylsilylmethyl Azide
Nicotinoyl Azide (NCA)-Mediated Mitsunobu Reaction: An Expedient One-Pot Transformation of Alcohols into Azides
作者:Gianluca Papeo、Helena Posteri、Paola Vianello、Mario Varasi
DOI:10.1055/s-2004-831254
日期:——
A practical and simple method that allows preparation of azides from alcohols is described. The process involves oxyphosphonium-type activation and it is based upon the use of nicotinoyl azide (NCA), a cheap and easily accessible azide ion source.
Chiroptical Probing of Lanthanide-Directed Self-Assembly Formation Using btp Ligands Formed in One-Pot Diazo-Transfer/Deprotection Click Reaction from Chiral Amines
作者:Joseph P. Byrne、Miguel Martínez-Calvo、Robert D. Peacock、Thorfinnur Gunnlaugsson
DOI:10.1002/chem.201504257
日期:2016.1.11
A series of enantiomeric 2,6‐bis(1,2,3‐triazol‐4‐yl)pyridines (btp)‐containing ligands was synthesized by a one‐pot two‐step copper‐catalyzed amine/alkyne clickreaction. The EuIII‐ and TbIII‐directed self‐assembly formation of these ligands was studied in CH3CN by monitoring their various photophysical properties, including their emerging circular dichroism and circularly polarized luminescence. The
A New Type of Oxidation-Reduction Condensation by the Combined Use of Phenyl Diphenylphosphinite and Oxidant
作者:Teruaki Mukaiyama、Kiichi Kuroda、Yuji Maruyama
DOI:10.3987/rev-09-sr(s)1
日期:——
A new type of oxidation-reduction condensation of alcohols with sulfur, nitrogen, and oxygen nucleophiles by the combined use of phenyl diphenylphosphinite (PhOPPh2) and oxidants such as azides or diethyl azodicarboxylate (DEAD) are described. In these reactions, chiral secondary and tertiary alcohols are converted into the corresponding chiral sulfides, azides, esters and ethers under mild and neutral conditions with almost complete inversion of stereochemical configuration.
Kinetic resolution by copper-catalyzed azide–alkyne cycloaddition
作者:Jun-cai Meng、Valery V. Fokin、M.G. Finn
DOI:10.1016/j.tetlet.2005.05.019
日期:2005.7
The use of chiral pybox ligands imparts enantioselectivity to the Cu-I-catalyzed azide-alkyne cycloaddition reaction, in the form of kinetic resolution of alpha-chiral azides and desymmetrization of gem-diazides. While levels of selectivity are modest, the results show unequivocally that the process benefits from ligand-accelerated catalysis. (c) 2005 Elsevier Ltd. All rights reserved.