Synthesis and determination of the absolute configuration of fugomycin and desoxyfugomycin: CD spectroscopy and fungicidal activity of butenolides.

@article{Braun2004SynthesisAD,
  title={Synthesis and determination of the absolute configuration of fugomycin and desoxyfugomycin: CD spectroscopy and fungicidal activity of butenolides.},
  author={Manfred Braun and Andreas Hohmann and Jaykumar Rahematpura and Corinna B{\"u}hne and Stefan Grimme},
  journal={Chemistry},
  year={2004},
  volume={10 18},
  pages={
          4584-93
        }
}
The dibromoalkenes (S)-3 and (R)- and (S)-4 are intermediates in the syntheses of the naturally occurring fungicidal butenolides fugomycin (1) and desoxyfugomycin (2), respectively. The stereoselective bromine-lithium exchange that leads to the carbenoid 12 and the vinyllithium reagent 17 a on the one hand, and palladium-catalyzed coupling reactions of the dibromoalkene 3 and the bromolactone 22 on the other are key steps en route to the butenolides 1 and 2. The chiral building blocks (S)-3, (R… 
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References

SHOWING 1-10 OF 61 REFERENCES
Stereoselective Synthesis of Highly Functionalized Cyclopropanes. Application to the Asymmetric Synthesis of (1S,2S)-2,3-Methanoamino Acids.
TLDR
Molecular mechanics calculations using a modified MM2 type force field adapted to the pi-allyl palladium complexes have explained the reversibility of the palladium-catalyzed cyclization step, responsible for the low enantioselectivity observed and for the formation of byproducts, i.e., azepine derivatives 8a,b arising from subsequent aza Cope ring expansion.
Synthesis of Enantiomeric N -(2-Phosphonomethoxypropyl) Derivatives of Purine and Pyrimidine Bases. II. The Synthon Approach
Another approach to ( R )- and ( S )- N -(2-phosphonomethoxypropyl) derivatives of purine and pyrimidine bases (PMP derivatives) I and II is described, consisting in alkylation of the heterocyclic
The Stille Reaction of 1,1-Dibromo-1-alkenes: Preparation of Trisubstituted Alkenes and Internal Alkynes.
  • W. Shen, Le Wang
  • Chemistry, Biology
    The Journal of organic chemistry
  • 1999
TLDR
This new method for internal alkyne preparation is general, requires very mild reaction conditions, and gives high yields.
Stereoselective Hydrogenolysis of 1,1-Dibromo-1-alkenes and Stereospecific Synthesis of Conjugated (Z)-Alkenyl Compounds
The Pd-catalyzed hydrogenolysis of 1,1-dibromoalkenes with Bu3SnH occurs at room temperature stereoselectively to give (Z)-1-bromo-1-alkenes. We sought to determine the optimal reaction conditions
Palladium-Catalyzed Cyclocarbonylation of Terminal and Internal Alkynols to 2(5H)-Furanones
A series of substituted alkynols, containing alkyl, phenyl, and vinyl groups at the acetylenic terminal, were found to undergo direct carbonylation to the corresponding substituted 2(5H)-furanones in
Chiral vinyl anions for «carbonyl umpolung». Highly stereoselective addition of a novel enantiomerically pure vinyllithium reagent to aldehydes
The vinyllithium reagent 13 and its enantiomer are generated by a bromine/lithium exchange reaction starting from dibromoalkenes 11 and 12, both available from the corresponding enantiomer of alkyl
Stereoselective radical additions of γ-oxy-α,β-unsaturated ester derivatives; 1,2-asymmetric induction in acyclic and cyclisation systems
Examination was made of 1,2-asymmetric induction in the addition of alkyl radicals to γ-oxy-α,β-unsaturated ester derivatives 1 and 2 prepared from ethyl lactate and
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