2010
Tapia-Benavides Antonio R., Mendoza-Huizar Luis H., Pérez-García Francisco, Tlahuext Hugo , Alvarez Alejandro, Tlahuextl Margarita*, Do spiroarsoranes exhibit polytopal equilibrium in solution?, Inorganic Chemistry, 49, 1496-1502 (2010). American Chemical Society ISSN: 0020-1669. FEB 15 2010
Abstract
The spiroarsoranes 5-phenyl-1,6-dioxa-4,9-diaza-5?5-arsaspiro[4.4]nonane (6), (3R,8R)-3,8-dimethyl-5-phenyl-1,6-dioxa-4,9-diaza-5?5-arsaspiro[4.4]nonane (7), (2S,7S)-2,7-dimethyl-5-phenyl-1,6-dioxa-4,9-diaza-5?5-arsaspiro[4.4]nonane (8), and (3S,8S)-3,8-dimethyl-(2R,7R)-2,5,7-triphenyl-1,6-dioxa-4,9-diaza-5?5-arsaspiro[4.4]nonane (9) were prepared by reaction of phenylarsonic acid and the correspondig amino alcohol. The presence of polytopal ? ? equilibrium in 6?9 was demonstrated by HPLC and NMR studies. NBO computations at the MP2/6-31+G(2d,2p) level indicate that methyl substitution in C2 or C3 of the oxazarsolane ring determines the predominance of ? or ? stereoisomers. GIAO B3LYP/6-311++G(2d,2p) computations were used to assign experimental 1H and 13C NMR spectra.
Et3B, an Efficient Mediator for Xanthate Transfer Based Radical Processes
Et3, and efficient Mediator for Xanthate Transfer Based Radical Processes.
Diastereoselective Synthesis of Spiro-?-lactams via Staudinger Reactio
Ylidaddukte der Penteltrichloride
Preparation of N-aryl-substituted spiro-?-lactams via Staudinger cycloaddition