The asymmetric synthesis of aryltetralin lignans: (−)-isolariciresinol dimethyl ether and (−)-deoxysikkimotoxin

1996 ◽  
Vol 74 (1) ◽  
pp. 88-94 ◽  
Author(s):  
Don M. Coltart ◽  
James L. Charlton
Keyword(s):  
Asymmetric Synthesis ◽  
Key Words ◽  
Dimethyl Ether ◽  
Selective Reduction ◽  
Diels Alder ◽  
Asymmetric Syntheses ◽  
One Pot ◽  
Synthetic Strategy

The total asymmetric syntheses of (−)-isolariciresinol dimethyl ether (6) and (−)-deoxysikkimotoxin (7) have been carried out, in an attempt to exploit a synthetic strategy recently developed for the synthesis of (−)-deoxypodophyllotoxin (1, R1 = -CH2−, Ar = 3,4,5-trimethoxyphenyl). In so doing, a generalized method for the synthesis of aryltetralin lignans has been developed that should be applicable to a variety of substitution patterns and stereochemistries. A one-pot, 100% regio-selective reduction–lactonization procedure has been developed for the conversion of the ester 18b to (−)-deoxysikkimotoxin, which gave 93% isolated yield in that step. Key words: ortho-quinodimethanes, lignans, Diels–Alder, asymmetric, mandelate.

scholarly journals Use of sultines in the asymmetric synthesis of polypropionate antibiotics

2008 ◽  
Vol 80 (4) ◽  
pp. 791-805 ◽  
Author(s):  
Pierre Vogel ◽  
Maris Turks ◽  
Laure Bouchez ◽  
Cotinica Craita ◽  
M. Carmen Murcia ◽  
...  
Keyword(s):  
Low Temperature ◽  
Asymmetric Synthesis ◽  
Acid Catalyst ◽  
Diels Alder ◽  
Chain Elongation ◽  
Acid Catalysts ◽  
Asymmetric Syntheses ◽  
One Pot ◽  
Biological Interest ◽  
Stereogenic Centers

At low temperature and in the presence of an acid catalyst, SO2 adds to 1,3-dienes equilibrating with the corresponding 3,6-dihydro-1,2-oxathiin-2-oxides (sultines). These compounds are unstable above -60 °C and equilibrate with the more stable 2,5-dihydrothiophene 1,1-dioxides (sulfolenes). The hetero-Diels-Alder additions of SO2 are suprafacial and follow the Alder endo rule. The sultines derived from 1-oxy-substituted and 1,3-dioxy-disubstituted 1,3-dienes cannot be observed at -100 °C but are believed to be formed faster than the corresponding sulfolenes. In the presence of acid catalysts, the 6-oxy-substituted sultines equilibrate with zwitterionic species that react with electron-rich alkenes such as enoxysilanes and allylsilanes, generating β,γ-unsaturated silyl sulfinates that can be desilylated and desulfinylated to generate polypropionate fragments containing up to three contiguous stereogenic centers and an (E)-alkene unit. Alternatively, the silyl sulfinates can be reacted with electrophiles to generate polyfunctional sulfones (one-pot, four-component synthesis of sulfones), or oxidized into sulfonyl chlorides and reacted with amines, then realizing a one-pot, four-component synthesis of polyfunctional sulfonamides. Using enantiomerically enriched dienes such as 1-[(R)- or 1-(S)-phenylethyloxy]-2-methyl-(E,E)-penta-1,3-dien-3-yl isobutyrate, derived from inexpensive (R)- or (S)-1-phenylethanol, enantiomerically enriched stereotriads are obtained in one-pot operations. The latter are ready for further chain elongation. This has permitted the development of expeditious total asymmetric syntheses of important natural products of biological interest such as the baconipyrones, rifamycin S, and apoptolidin A.

Cyclic Alkyne Approach to Heteroatom-Containing Polycyclic Aromatic Hydrocarbon Scaffolds

2019 ◽  
Author(s):  
Evan Darzi ◽  
Joyann Barber ◽  
Neil Garg
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbons ◽  
Diels Alder ◽  
Pericyclic Reactions ◽  
One Pot ◽  
Synthetic Strategy ◽  
Polycyclic Aromatic

We report a modular synthetic strategy for accessing heteroatom-containing polycyclic aromatic hydrocarbons (PAHs) that relies on the controlled generation of transient heterocyclic alkynes and arynes. The strained intermediates undergo in situ trapping with readily accessible oxadiazinones. Four sequential pericyclic reactions occur, namely two Diels–Alder / retro-Diels–Alder sequences, which can be performed in a stepwise or one-pot fashion to assemble four new carbon–carbon (C–C) bonds.

An Efficient One-Pot Asymmetric Synthesis of Biaryl Compounds via Diels−Alder/Retro-Diels−Alder Cascade Reactions

2007 ◽  
Vol 9 (5) ◽  
pp. 805-808 ◽  
Author(s):  
Yongxiang Liu ◽  
Kui Lu ◽  
Mingji Dai ◽  
Kai Wang ◽  
Wanqing Wu ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Cascade Reactions ◽  
Diels Alder ◽  
One Pot ◽  
Biaryl Compounds

scholarly journals An Efficient One-Pot Asymmetric Synthesis of Biaryl Compounds via Diels—Alder/Retro-Diels—Alder Cascade Reactions.

ChemInform ◽  
2007 ◽  
Vol 38 (29) ◽  
Author(s):  
Yongxiang Liu ◽  
Kui Li ◽  
Mingji Dai ◽  
Kai Wang ◽  
Wanqing Wu ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Cascade Reactions ◽  
Diels Alder ◽  
One Pot ◽  
Biaryl Compounds

Cyclic Alkyne Approach to Heteroatom-Containing Polycyclic Aromatic Hydrocarbon Scaffolds

2019 ◽  
Author(s):  
Evan Darzi ◽  
Joyann Barber ◽  
Neil Garg
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbons ◽  
Diels Alder ◽  
Pericyclic Reactions ◽  
One Pot ◽  
Synthetic Strategy ◽  
Polycyclic Aromatic

We report a modular synthetic strategy for accessing heteroatom-containing polycyclic aromatic hydrocarbons (PAHs) that relies on the controlled generation of transient heterocyclic alkynes and arynes. The strained intermediates undergo in situ trapping with readily accessible oxadiazinones. Four sequential pericyclic reactions occur, namely two Diels–Alder / retro-Diels–Alder sequences, which can be performed in a stepwise or one-pot fashion to assemble four new carbon–carbon (C–C) bonds.

scholarly journals Stereocontrolled asymmetric synthesis

2000 ◽  
Vol 72 (9) ◽  
pp. 1691-1697 ◽  
Author(s):  
Yong Hae Kim ◽  
Sam Min Kim ◽  
Doo Han Park ◽  
So Won Youn
Keyword(s):  
Asymmetric Synthesis ◽  
Lewis Acid ◽  
Diels Alder ◽  
Samarium Diiodide ◽  
Coupling Reactions ◽  
Asymmetric Syntheses ◽  
Pinacol Coupling ◽  
First Time

Stereo differentiated asymmetric syntheses have been achieved by S-indoline derivations. Diels-Alder cycloadditions of S-indoline chiral acrylamides with cyclopentadiene proceed with high diastereofacial selectivity, giving either endo-R or endo-S products depending on Lewis acid and the structures of chiral dienophiles. Diastereo- and enantio-selective pinacol coupling reactions of chiral α-ketoamides mediated by samarium diiodide afforded extremely high diastereoselectivities. Enantiopure (S,S)- or (R,R)-2,3-dialkyltar-taric acid and derivatives can be synthesized for the first time depending on the structure of α-ketoamides.

One-pot, highly efficient, asymmetric synthesis of ring-fused piperidine derivatives bearing N,O- or N,N-acetal moieties

2016 ◽  
Vol 14 (8) ◽  
pp. 2444-2453 ◽  
Author(s):  
Ji-Yao Li ◽  
Zhi-Long Li ◽  
Wei-Wei Zhao ◽  
Yan-Kai Liu ◽  
Zhi-Ping Tong ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Alder Reaction ◽  
Diels Alder ◽  
One Pot ◽  
Highly Efficient ◽  
Diels Alder Reaction

Lactols or cyclic hemiaminals are directly used as nucleophiles in the asymmetric aza-Diels–Alder reaction to synthesize ring-fused piperidine derivatives.

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