Unsymmetrical Ozonolysis of a Diels−Alder Adduct:  Practical Preparation of a Key Intermediate for Heme Total Synthesis

2001 ◽  
Vol 66 (7) ◽  
pp. 2515-2517 ◽  
Author(s):  
Douglass F. Taber ◽  
Katsumasa Nakajima
Keyword(s):  
Total Synthesis ◽  
Diels Alder ◽  
Alder Adduct

scholarly journals Cover Picture: Total Synthesis Confirms Laetirobin as a Formal Diels-Alder Adduct (Chem. Asian J. 2/2010)

2010 ◽  
Vol 5 (2) ◽  
pp. 185-185
Author(s):  
Oliver Simon ◽  
Bastien Reux ◽  
James J. La Clair ◽  
Martin J. Lear
Keyword(s):  
Total Synthesis ◽  
Diels Alder ◽  
Alder Adduct

Total Synthesis Confirms Laetirobin as a Formal Diels-Alder Adduct

2010 ◽  
Vol 5 (2) ◽  
pp. 342-351 ◽  
Author(s):  
Oliver Simon ◽  
Bastien Reux ◽  
James J. La Clair ◽  
Martin J. Lear
Keyword(s):  
Total Synthesis ◽  
Diels Alder ◽  
Alder Adduct

A Total Synthesis of Dimethyl 2,3-O-Isopropylidene-l-O-oxalyl-β-DL-ribo-hexofuran-5-ulosuronate

1975 ◽  
Vol 53 (18) ◽  
pp. 2701-2706 ◽  
Author(s):  
George Just ◽  
Karl Grozinger
Keyword(s):  
Total Synthesis ◽  
Title Compound ◽  
Catalytic Reduction ◽  
Major Product ◽  
Diels Alder ◽  
High Yield ◽  
Thermal Rearrangement ◽  
Dimethyl Acetylenedicarboxylate ◽  
Alder Adduct

The synthesis of the title compound 5 was accomplished by a high-yield thermal rearrangement of the ozonide (3) of dimethyl 5,6-O-isopropylidene-7-oxabicyclo[2.2.1]hept-2-ene-exo-5,6-diol-2,3-dicarboxylate (2a), which is obtained in 30% yield from the Diels–Alder adduct of furan and dimethyl acetylenedicarboxylate. Catalytic reduction of 5 gave methyl 2,3-O-iso-propylidene-β-DL-talofuranuronate (8) as the major product, accompanied by a small amount of the allo isomer 9.

Bridged-ring steroids. V. The total synthesis of 1,4-methano steroids by a modified Torgov sequence

1988 ◽  
Vol 66 (9) ◽  
pp. 2268-2278 ◽  
Author(s):  
Peter Yates ◽  
Stephen P. Douglas ◽  
Sushil K. Datta ◽  
Jeffrey F. Sawyer
Keyword(s):  
Total Synthesis ◽  
Sodium Borohydride ◽  
Potassium Hydroxide ◽  
Hydrolysis Product ◽  
Diels Alder ◽  
Allylic Alcohol ◽  
Hydroxy Derivative ◽  
Enol Ether ◽  
Zinc Amalgam ◽  
Alder Adduct

The Diels–Alder adduct, 17, of cyclopentadiene and 2-methoxy-5-methyl-1,4-benzoquinone was reduced with sodium borohydride to the ketol 18, whose acetate 19 was further reduced with zinc amalgam to the monoketone 20. Reaction of 20 with vinyllithium gave the allylic alcohol 21, which underwent very ready dehydration with rearrangement to give the tricyclic enol ether 27, which was hydrolyzed to ketone 28a. Hydrogenation of 19 gave the dihydro product 30, which was reduced with zinc amalgam to the ketone 31. Treatment of the latter with vinyllithium gave the allylic alcohol 32. This was more stable than its analogue 21, but underwent hydrolysis and dehydration to the dienone 33. Treatment of 32 with 2-methyl-1,3-cyclo-pentanedione (5) in the presence of Triton B gave the tricyclic intermediate 35, its hydrolysis product 36, and the hydroxy derivative of the latter, 37. In the absence of base, 32 and 5 gave largely product 36. Hydrogenation of 36 gave the dihydro product 38, which on treatment with methanolic potassium hydroxide gave (±)-(1β,4β,5β,8α,9β,10β,13β,14β)-14-hydroxy-1,4-methanoandrostane-7,17-dione (39). Dehydration of 39 with p-toluenesulfonic acid gave first (±)-(1β,4β,5β,9β,10β,13β)-1,4-methanoandrost-8(14)-ene-7,17-dione (40), which was converted in turn to (±)-(1β,4β,5β,8α,9β,10β,13β,14β)-1,4-methanoandrost-15-ene-7,17-dione (41). Similar dehydration of 36 gave (±)-(1β,4β,5β,10β,13β,14β)-1,4-methanoandrosta-8,15-diene-7,17-dione (45).

scholarly journals Synthetic Studies of Diels–Alder Adduct of Furan. Formal Total Synthesis of (±)-Avenaciolide

1986 ◽  
Vol 59 (12) ◽  
pp. 3881-3884 ◽  
Author(s):  
Hiyoshizo Kotsuki ◽  
Hiroyuki Ohnishi ◽  
Yasuhiro Akitomo ◽  
Masamitsu Ochi
Keyword(s):  
Total Synthesis ◽  
Diels Alder ◽  
Synthetic Studies ◽  
Alder Adduct

Synthesis of erythrina and related alkaloids. 17. Total synthesis of dl-coccuvinine and dl-coccolinine

1987 ◽  
Vol 65 (1) ◽  
pp. 94-98 ◽  
Author(s):  
Takehiro Sano ◽  
Jun Toda ◽  
Nobuteru Maehara ◽  
Yoshisuke Tsuda
Keyword(s):  
Total Synthesis ◽  
Aromatic Ring ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction ◽  
Alder Adduct

Total synthesis of dl-coccuvinine 1a and dl-coccolinine 2a, "abnormal-type" erythrinan alkaloids lacking the C(16) O-function at the aromatic ring, was effectively achieved by using the Diels–Alder reaction of dioxopyrroline. Isoquinolinopyrrolinedione 6a, a key dienophile, was synthesized via the tetrahydroisoquinoline 5a, which was prepared by Bischler–Napieralski cyclization of the amide 4a at the unactivated position. The Diels–Alder adduct 7a of 1,3-bis(trimethylsilyloxy)-butadiene with 6a with converted stereoselectively into these alkaloids in short steps.

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