Tandem Dipolar Cycloaddition−Mannich Cyclization as an Approach to Tricyclic Nitrogen Heterocycles
作者:Albert Padwa、Michael A. Brodney、Joseph P. Marino、Martin H. Osterhout、Alan T. Price
DOI:10.1021/jo9607267
日期:1997.1.1
stereochemistry of the resulting A/B ring fusion is analogous to similar erythrinane products obtained via a Mondon-enamide-type cyclization. The stereochemical assignment of the final cyclized products was determined by X-ray crystallography. Molecularmechanicscalculations show that the ground state energy of the cis-fused diastereomer is 4.6 kcal lower than that of the trans diastereomer, and presumably some
Indium metal as a reducing agent in organic synthesis
作者:Michael R. Pitts、Justin R. Harrison、Christopher J. Moody
DOI:10.1039/b101712h
日期:——
aromatic nitrocompounds under similar conditions results in selectivereduction of the nitro groups; ester, nitrile, amide and halide substituents are unaffected. Likewise indium in aqueous ethanolic ammonium chloride is an effective method for the deprotection of 4-nitrobenzyl ethers and esters. Indium is also an effective reducing agent under non-aqueous conditions and α-oximino carbonyl compounds can