Synthesis of Chemically and Configurationally Stable Monofluoro Acylboronates: Effect of Ligand Structure on their Formation, Properties, and Reactivities
作者:Hidetoshi Noda、Jeffrey W. Bode
DOI:10.1021/jacs.5b00822
日期:2015.3.25
tetravalent, configurationally stable B-chiral acylboronates. Significantly, the ligands on the boronate allow for fine-tuning of the properties and reactivity of acylboronates. In amide-formingligation with hydroxylamines under aqueous conditions, a considerable difference in reactivity was observed as a function of ligand structure. The solid-state structures suggested that subtle steric and conformational
Chemoselective <i>N</i>-Acylation via Condensations of <i>N</i>-(Benzoyloxy)amines and α-Ketophosphonic Acids under Aqueous Conditions
作者:Jasbir Singh Arora、Navneet Kaur、Otto Phanstiel IV
DOI:10.1021/jo800223j
日期:2008.8.1
22% yield upon addition of 2 equiv of TFA. The N-acylation reaction is highly chemoselective for N-benzoyloxyamines as both aliphatic amines and N-hydroxylamines were shown not to react productively with the α-ketophosphonic acids under the conditions tested. Moreover, the α-ketophosphonic acids are more selective than the related α-ketocarboxylic acid systems, which react with both the N-hydroxylamines
Diastereoselectivity of organometallic additions to nitrones bearing stereogenic N-substituents
作者:Zen Yu Chang、Robert M. Coates
DOI:10.1021/jo00298a018
日期:1990.5
CHANG, ZEN-YU;COATES, ROBERT M., J. ORG. CHEM., 55,(1990) N1, C. 3464-3474
作者:CHANG, ZEN-YU、COATES, ROBERT M.
DOI:——
日期:——
Asymmetric α-oxyacylation of cyclic ketones
作者:Deborah A. Smithen、Christopher J. Mathews、Nicholas C. O. Tomkinson
DOI:10.1039/c2ob25293g
日期:——
Reaction of cyclic ketones with chiral N-alkyl-O-acyl hydroxylamines leads to the corresponding α-oxyacylated carbonyl compound in up to 89% ee. The levels of asymmetric induction were influenced by solvent polarity, acid strength and, to a lesser extent, temperature. Increasing the steric bulk around the nitrogen atom of the hydroxylamine reagent led to increased levels of asymmetric induction, which was also found to be detrimental to the yield observed for the transformation. Examination of N- and O-substituents along with substrates revealed the scope and limitations of the procedure.