Dinuclear gold(I)‐N‐heterocyclic carbene complexes: Synthesis, characterization, and catalytic application for hydrohydrazidation of terminal alkynes
作者:Seema Yadav、Sriparna Ray、Ajeet Singh、Shaikh M. Mobin、Tapta Kanchan Roy、Chandrakanta Dash
DOI:10.1002/aoc.5942
日期:2020.11
Dinuclear gold(I)‐N‐heterocyclic carbenecomplexes were developed for the hydrohydrazidation of terminal alkynes. The gold(I)‐N‐heterocyclic carbenecomplexes 2a‐2b were synthesized in good yields from silver complexes synthesized in situ, which in turn were obtained from the corresponding imidazolium salts with Ag2O in dichloromethane as a solvent. The new air‐stable gold(I)‐NHCcomplexes, 2a‐2b, were
Enantioselective Allylation of Ketone-Derived Benzoylhydrazones: Practical Synthesis of Tertiary Carbinamines
作者:Richard Berger、Keiko Duff、James L. Leighton
DOI:10.1021/ja0486418
日期:2004.5.1
A highly practical method for the enantioselective allylation of ketone-derived benzoylhydrazones has been developed. The previously reported strained silacycle reagent 1 reacts with a wide variety of benzoylhydrazones to give the hydrazide products with good to excellent enantioselectivity (84-97% ee). A mechanism in which the acylhydrazone becomes caovalently attached to the silane has been established
The invention concerns a water soluble compound of formula (a) wherein: A represents naphthyl or phenyl; and Ar
1
and Ar
2
independently represent a saturated or aromatic carbocyclic group; X
a
, X
b
are independently selected among an amino group, an ammonium group and an amino group modified by a linear polyoxyalkylene chain, provided that at least one of X
a
and X
b
represents ammonium or modified amino.
Enantioselective hydrogenation of the C:N group: a catalytic asymmetric reductive amination procedure
作者:Mark J. Burk、John E. Feaster
DOI:10.1021/ja00041a067
日期:1992.7
substituents on phosphorus-linked aryl groups dramatically enhance the enantioselectivity. Such electronic effects of ligands on the enantioselectivity are rare, and as in the welldocumented case of Mn(II1)-mediated epoxidation reactions,' these may play an important role in the design of new catalysts. The highest enantioselectivities are obtained in nonpolar solvents (C6F6 = hexane > benzene > THF),
Allyltrichlorosilanes reacted with benzoylhydrazones in DMF without the use of any catalyst to afford the corresponding homoallylic benzoylhydrazines in good to high yields. The reactions proceeded at 0 degrees C to room temperature under mild conditions. In addition, it was found that the reactions tolerated well the steric hindrance of hydrazones and allyltrichlorosilanes. Indeed, ketone-derived