Enantioselective synthesis of (+)- and (-)-dihydroepiepoformin and (+)-epiepoformin.

@article{Carreo2005EnantioselectiveSO,
  title={Enantioselective synthesis of (+)- and (-)-dihydroepiepoformin and (+)-epiepoformin.},
  author={M. Carmen Carre{\~n}o and Est{\'i}baliz Merino and Mar{\'i}a Ribagorda and {\'A}lvaro Somoza and Antonio Urbano},
  journal={Organic letters},
  year={2005},
  volume={7 7},
  pages={
          1419-22
        }
}
[reaction: see text] The enantioselective synthesis of both enantiomers of dihydroepiepoformin (1) and (+)-epiepoformin (2) was achieved from (p-tolylsulfinyl)methyl-p-quinols (SR)- or (SS)-3 and (4R,SR)-4, respectively. Key features include the stereocontrolled conjugate addition of AlMe3 to p-quinol 3 and retrocondensation to the ketone functionality, previous to oxidation of the beta-hydroxy sulfoxide moiety of advanced intermediates to the corresponding sulfone. 
26 Citations
A Stereoselective Approach to Functionalized Cyclohexenones
A catalytic enantioselective approach to 4-hydroxy-6-methylcyclohex-2-enones is presented herein. The stereogenic information is generated through a copper-catalyzed 1,4-addition to p-benzoquinone
Asymmetric synthesis of rubiginones A(2) and C(2) and their 11-methoxy regioisomers.
TLDR
Key steps in the synthesis of this diene were the stereoselective conjugate addition of AlMe(3) on (SS)-[(p-tolylsulfinyl)methyl]-p-quinol (9) and the elimination of the beta-hydroxy sulfoxide fragment, after oxidation to sulfone, to recover a carbonyl group.
Enantioselective synthesis of natural polyoxygenated cyclohexanes and cyclohexenes from [(p-tolylsulfinyl)methyl]-p-quinols.
TLDR
The limitations of the use of the beta-hydroxy sulfoxide as a chiral protecting carbonyl group were demonstrated, dependent on the relative stabilities of the final targets in the presence of the required base.
Total synthesis of (±)-cycloclavine and (±)-5-epi-cycloclavine.
Novel routes to the naturally occurring indole alkaloid cycloclavine and its unnatural C(5)-epimer are described. Key features include the rapid construction of the heterocyclic core segments by two
Reactions of p‐Quinols with Aldehydes and Imines: Stereoselective Access to Polyheterobicyclic and Tricyclic Systems
Dihydrobenzo[1,3]dioxolanones, tetrahydrobenzo[d]oxazolones and heterotricyclic derivatives have been stereoselectively synthesized from p-quinols upon reaction with aldehydes or benzaldimines under
Highly Efficient Synthesis of (+)-Bromoxone, (+)-Epiepoxydon and (+)-Epiepoformin
), isolated from the culture filtrate of an unidentified fungus, showed inhibitory activity against the germination of lettuce seeds. Due to their broad range of biological properties and their
Total synthesis of malyngamides K, L, and 5''-epi-C and absolute configuration of malyngamide L.
An accelerated, enantioselective, and general synthetic route to a class of malyngamides, K (1), L (3), and 5''-epi-C (4), bearing a cyclohexenone ring or a heavily oxygenated six-membered ring and a
Friedel-Crafts Alkylation of Indoles with p-Quinols: The Role of Hydrogen Bonding of Water for the Desymmetrization of the Cyclohexadienone System.
TLDR
Experimental results and theoretical calculations explained the enantioselectivity based on a transition state where two water molecules act as a tether joining the p-quinol with the phosphoric acid and the NH of indole, thus facilitating the desymmetrization of the prochiral cyclohexadienone framework.
Towards configurationally stable [4]helicenes: enantioselective synthesis of 12-substituted 7,8-dihydro[4]helicene quinones.
TLDR
Evidence is provided that, in addition to steric effects, a small but significant role of electronic effects is governing the configurational stability of such helical quinones.
...
...

References

SHOWING 1-10 OF 22 REFERENCES
Studies of Diastereoselectivity in Conjugate Addition of Organoaluminum Reagents to (R)-[(p-Tolylsulfinyl)methyl]quinols and Derivatives
(R)-4-Hydroxy-4-[(p-tolylsulfinyl)methyl]-2,5-cyclohexadienones 1−3, and 6 reacted with organoaluminum derivatives from the pro-R conjugated position in a highly π-facial diastereoselective manner
The first synthesis of (-)-asperpentyn and efficient syntheses of (+)-harveynone, (+)-epiepoformin and (-)-theobroxide.
TLDR
The enantioselective syntheses of (-)-theobroxide, a polyoxygenated cyclohexane natural compound with potent growth inducing properties in potato microtubers has been achieved via a 1,2 O-silyl migration between trans-hydroxyl groups and a remote hydroxyl directed epoxidation of an enone derived from quinic acid.
A convenient stereoselective synthesis of syn-bishomoquinone (tri-cyclo[5,1,0,0]octane-2,6-dione)
Reaction of 4,4-dimethoxycyclohexa-2,5-dienone with dimethylsulphoxonium methylide and subsequent hydrolysis gave exclusively syn-bishomoquinone. An attempted double addition of carbene to
π-Facial Diastereoselection in Diels−Alder Reactions of (R)-4-[(p-Tolylsulfinyl)methyl]quinols
Diels−Alder reactions of a range of (R)-4-hydroxy-4-[(p-tolylsulfinyl)methyl]-2,5-cyclohexadienones with cyclopentadiene and 1,3-pentadiene proceed in a total π-facial diastereoselective manner from
beta-Hydroxysulfoxides as chiral cyclic ketone equivalents: enantioselective synthesis of polysubstituted cyclohexanones, cyclohexenones and cyclohexenediones.
The beta-hydroxysulfoxide moiety, after oxidation to sulfone, acts as a masked carbonyl group in a cyclic system, opening an easy access to differently substituted enantiomerically pure cyclic
...
...