Pyrroloisoxazoles as a Building Block for 3-Enoyltetramic Acids
作者:Raymond Jones、Terence Pillainayagam
DOI:10.1055/s-2004-835640
日期:——
3-Methylpyrrolo[3,4-c]isoxazoles prepared by nitrile oxide cycloaddition, are deprotonated and condensed with aromatic aldehydes; N-O bond cleavage with Mo(CO)6 affords 3-enoyltetramic acids whilst with H2-catalyst further reduction to 3-acyltetramic acids is observed.
Dichotomy of Enamines at the C⋮C Bond of a (1-Alkynyl)carbene Tungsten Complex. (1-Azoniabutadien-4-yl)carbonylmetalates (<sup>-</sup>OC)<sub>5</sub>WC(OEt)CR<sup>1</sup>C(N<sup>+</sup>R<sub>2</sub>)Me, Stable Torsion Isomers of (2-Aminoethenyl)carbene Complexes (OC)<sub>5</sub>WC(OEt)CR<sup>1</sup>C(NR<sub>2</sub>)Me<sup>1</sup>
作者:Rudolf Aumann、Klaus Roths、Roland Fröhlich
DOI:10.1021/om9707782
日期:1997.12.1
R1 = Ph, CO2Me, CO2Et, CO2Bz, CO2-t-Bu] to the 1-alkynylcarbene complex (CO)5WC(OEt)C⋮CPh (1a) affords novel (1-azoniabutadien-4-yl)carbonylmetalates (-OC)5WC(OEt)C[C(N+R2)Me]C(Ph)CHR1 (2E)-torquo-8a−f by dichotomy of the CC(N) bond of 8 at the C⋮C bond of 1. Compounds (2E)-torquo-8 are stable in solid state but undergo (2E/2Z) isomerization in solution to give compounds (2Z)-torquo-8. X-ray structure
Transition-metal-free synthesis of 3-(1-pyrrolidinyl)quinolines and 3-(1-pyrrolidinyl)quinoline 1-oxides via a one-pot reaction of 3-(1-pyrrolidinyl)crotonates with nitrobenzenes
tert-butyl 3-(1-pyrrolidinyl)crotonate adds to nitrobenzenes to form σH-adducts, which in the presence of pivaloyl chloride and triethylamine are converted into 3-(1-pyrrolidinyl)quinolines or 3-(1-pyrrolidinyl)quinoline 1-oxides depending on the nitrobenzene structure. This is the first methodology in which a quinoline ring is constructed from a substrate bearing a pyrrolidinyl ring. Starting from optically
Several new β-amino esters were prepared in two simple steps from β-keto ester derivatives and primary and secondary amines under mild conditions. The hydrogenation of various enamino esters was performed at 50 ËC in the presence of iridium catalysts. The new β-N-substituted amino esters were isolated in high yields.