𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Simple and condensed β-lactams, part 31. Acid catalyzed ring closures and ring transformations of some 3-aryloxy-4-oxoazetidine-2-carbaldehydes

✍ Scribed by Ferenc Bertha; József Fetter; Mária Kajtár-Peredy; Károly Lempert; Gábor Czira

Publisher
Elsevier Science
Year
1998
Tongue
French
Weight
887 KB
Volume
54
Category
Article
ISSN
0040-4020

No coin nor oath required. For personal study only.

✦ Synopsis

Carbaldehydes la and lb, when treated with Lewis or Bronsted acids in non-aromatic solvents or in nitrobenzene afford dihydrochromeno[3,2-b]azet-2(IH)-ones of types 4-6 and 10. In toluene, chloro-and fluoro-benzene related compounds of types 7-9 were obtained, in the last named two solvents accompanied by pyrrolidin-2-one derivatives 11-15.

📜 SIMILAR VOLUMES

Simple and condensed β-lactams. Part 33.
Simple and condensed β-lactams. Part 33. AlCl3 catalyzed ring closures of some 3-aryloxy-4-oxoazetidine-2-carboxylic chlorides to 1H-chromeno[3,2-b]azete-2,8(2aH,8aH)-diones and some reactions of the products
✍ Ferenc Bertha; József Fetter; Mária Kajtár-Peredy; Károly Lempert 📂 Article 📅 1999 🏛 Elsevier Science 🌐 French ⚖ 749 KB

Carboxylic chlorides 3a-3c, when treated with AIC13, afforded the tricyclic compounds 17a-17c. NaBH4 reduction of 17a and 17b afforded compounds 1 la and lib. The latter and the related known compounds 4a, 5b, 6a and 7a were used for the preparation of various dihydrochromeno[3,2-b]azet-2(lH)-ones a

Simple and condensed β-lactams. Part 29.
Simple and condensed β-lactams. Part 29. Synthesis and base-catalyzed ring transformation of 4-[(2RS,3SR)-3-hydroxy-1-(4-methoxyphenyl)-4-oxoazetidin-2-yl)]thiazol-2(3H)-one
✍ Attila Sápi; József Fetter; Károly Lempert; Mária Kajtár-Peredy; Gábor Czira 📂 Article 📅 1997 🏛 Elsevier Science 🌐 French ⚖ 441 KB

4-[(2RS,3R,S)-3-Hydroxy-(lb) and -3-(4-chlomphenoxy)-l-(4-methoxyphenyl)-4-oxoazetidin-2-yl]thiazol-2(3H)-one (16b) were synthesised. While the former was smoothly rearranged into (5RA•-5-hydr•xy-7-(4-meth•xypheny•)-••5-dihydr•thiaz•••[3.4-a•pyrazine-3•6(7H)-di•ne (7b) on treatment with Na2CO3 unde