An asymmetric synthesis of 2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (ADTN)

1990 ◽  
Vol 68 (11) ◽  
pp. 2028-2032 ◽  
Author(s):  
James L. Charlton ◽  
Kevin Koh ◽  
Guy L. Plourde
Keyword(s):  
Asymmetric Synthesis ◽  
Title Compound ◽  
Optical Purity ◽  
Diels Alder ◽  
Methyl Lactate

An asymmetric synthesis of 2-amino-6,7-dimethoxy-1,2,3,4-tetrahydronaphthalene, which can be converted to the title compound by a literature procedure, is described. The synthesis, starting from 2-amino-4,5-dimethoxybenzoic acid and the acrylate of S-methyl lactate, was accomplished in eight steps in 11% overall yield and > 97% optical purity. Keywords: o-quinodimethanes, Diels–Alder, asymmetric, cycloaddition, induction, diastereoselective, ADTN.

Diels–Alder addition of the fumarate and acrylate of S-methyl lactate to α-hydroxy orthoquinodimethanes

1989 ◽  
Vol 67 (4) ◽  
pp. 574-579 ◽  
Author(s):  
James L. Charlton ◽  
Guy L. Plourde ◽  
Kevin Koh ◽  
Anthony S. Secco
Keyword(s):  
Asymmetric Synthesis ◽  
Optical Purity ◽  
Diels Alder ◽  
Asymmetric Induction ◽  
Synthetic Route ◽  
Methyl Lactate ◽  
High Optical Purity ◽  
Single Diastereomer ◽  
Potential Use

The cycloaddition of α-hydroxy orthoquinodimethane, generated photochemically from 2-methylbenzaldehyde, to the fumarate and acrylate of S-methyl lactate has been found to give a single diastereomer with high asymmetric induction (>95% de). This reaction provides a new and versatile synthetic route to substituted tetralins of high optical purity. A trans stereochemistry between the vicinal hydroxyl and carboxylactyl groups has been established for these cycloadducts. This is in contrast to previous work where cis stereochemistry has always been found for major cycloadducts of α-hydroxy o-QDMs. The high asymmetric induction, unusual diastereoselectivity, and the potential use of these reactions in asymmetric synthesis are discussed. Keywords: o-quinodimethanes, Diels–Alder, asymmetric, cycloaddition, induction, diastereoselective.

Asymmetric synthesis of podophyllotoxin analogs

1990 ◽  
Vol 68 (11) ◽  
pp. 2022-2027 ◽  
Author(s):  
James L. Charlton ◽  
Guy L. Plourde ◽  
K. Koh ◽  
Anthony S. Secco
Keyword(s):  
Asymmetric Synthesis ◽  
Natural Product ◽  
Good Yield ◽  
Diels Alder ◽  
Cycloaddition Reactions ◽  
Thermal Generation ◽  
Methyl Lactate ◽  
Model Studies ◽  
Diastereomeric Excess ◽  
Absolute Stereochemistry

Two analogs of podophyllotoxin, with the same absolute stereochemistry as the natural product, have been synthesized from the cycloadduct between α-hydroxy-α′-phenyl-o-quinodimefhane and the fumarate of S-methyl lactate. After initial attempts to produce the cycloadduct from photochemically generated α-hydroxy-α′-phenyl-o-quinodimethane failed, a study of the thermal generation and reaction of α-hydroxy-o-quinodimethane with the fumarate and acrylate of S-methyl lactate was made. A comparison was made of the diastereoselectivity of these cycloaddition reactions to those previously reported, in which the o-quinodimethane was generated photochemically. The α-hydroxy-o-quinodimethane was produced both by the known thermolysis of benzocyclobutenol and by thermolysis of 1-hydroxy-1,3-dihydrobenzo[c]thiophene-2,2-dioxide. The diastereomeric excess for the cycloaddition reactions was found to be greater than 95% with modest (ca. 55%) isolated yields of the major cycloadducts. Following these model studies, it was found that α-hydroxy-α′-phenyl-o-quinodimethane produced thermally from 1-hydroxy-3-phenyl-1,3-dihydrobenzo[c]thiophene-2,2-dioxide could be added to the fumarate of S-methyl lactate with high diastereoselectivity and good yield. The product of this reaction was converted to the podophyllotoxin analogs 7 and 17. Keywords: o-quinodimethanes, asymmetric, Diels–Alder, lactate, podophyllotoxin, lignan.

Asymmetric Synthesis of Fused Tetrahydroquinolines via Intramolecular Aza-Diels-Alder Reaction of ortho-Quinone Methide Imines

Synthesis ◽  
2021 ◽  
Author(s):  
Fabian Hofmann ◽  
Cornelius Gärtner ◽  
Martin Kretzschmar ◽  
Christoph Schneider
Keyword(s):  
Asymmetric Synthesis ◽  
Alder Reaction ◽  
Single Step ◽  
Diels Alder ◽  
Quinone Methide ◽  
Bronsted Acid ◽  
Atom Economy ◽  
Diels Alder Reaction ◽  
Brönsted Acid ◽  
Chiral Bronsted Acid

Aza-Diels Alder reactions are straightforward processes in the construction of N-heterocycles, featuring inherent atom-economy and stereospecificity. Intramolecular strategies allow formation of bicyclic core structures with up to three stereocenters within a single step. Herein, this concept is combined with the chemistry of chiral Brønsted acid-bound ortho-quinone methide imines generating a range of interesting fused tetrahydro-quinolines in a diastereo- and enantioselective manner.

scholarly journals Enantioselective Organocatalytic Intramolecular Diels—Alder Reactions. The Asymmetric Synthesis of Solanapyrone D.

ChemInform ◽  
2005 ◽  
Vol 36 (52) ◽  
Author(s):  
Rebecca M. Wilson ◽  
Wendy S. Jen ◽  
David W. C. MacMillan
Keyword(s):  
Asymmetric Synthesis ◽  
Diels Alder

Asymmetric synthesis of N-phenylethyl-2-phenyldecahydroquinolin-4-ones via Lewis acid catalyzed imino-Diels–Alder reaction

2000 ◽  
Vol 11 (12) ◽  
pp. 2509-2523 ◽  
Author(s):  
Renée Paugam ◽  
Emmanuelle Valenciennes ◽  
Linda Le Coz-Bardol ◽  
Jean-Christophe Garde ◽  
Lya Wartski ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Lewis Acid ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction ◽  
Acid Catalyzed

Asymmetric synthesis of isoquinuclidines by Diels–Alder reaction of 1,2-dihydropyridine utilizing a chiral Lewis acid catalyst

Tetrahedron ◽  
2012 ◽  
Vol 68 (6) ◽  
pp. 1774-1781 ◽  
Author(s):  
Chigusa Seki ◽  
Masafumi Hirama ◽  
N.D.M. Romauli Hutabarat ◽  
Junko Takada ◽  
Chonticha Suttibut ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Lewis Acid ◽  
Acid Catalyst ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction ◽  
Chiral Lewis Acid ◽  
Lewis Acid Catalyst

1-[(E)-Butadienylsulfonyl]-3,3-dimethylbut-2-yl methacrylate

2006 ◽  
Vol 62 (4) ◽  
pp. o1369-o1370 ◽  
Author(s):  
Matthias Zeller ◽  
Allen D. Hunter ◽  
Paul Sampson ◽  
Nataliya Chumachenko
Keyword(s):  
Solid State ◽  
Title Compound ◽  
Diels Alder ◽  
Cycloaddition Reactions ◽  
Compound C

The title compound, C14H22O4S, was synthesized as a precursor for intramolecular Diels–Alder cycloaddition reactions. The (E)-buta-1,3-dienyl and methacrylate ester systems adopt an s–trans conformation in the solid state, with the two π units in both cases being almost coplanar.

ChemInform Abstract: Studies in Asymmetric Synthesis. Part 4. Studies in Lewis Acid and LiClO4 (or Nafion-H) Catalyzed Ionic Diels-Alder Reactions of Chiral and Achiral Olefinic Acetals Respectively.

ChemInform ◽  
2010 ◽  
Vol 30 (27) ◽  
pp. no-no
Author(s):  
R. Kumareswaran ◽  
Padma S. Vankar ◽  
M. Venkat Ram Reddy ◽  
Sangeeta V. Pitre ◽  
Raja Roy ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Lewis Acid ◽  
Diels Alder
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