✦ LIBER ✦

Regio- and Stereoselective Reduction of 3,5-Disubstituted 3a,6a-Dihydro-4H-pyrrolo[3,4-d]isoxazole-4,6(5H)-diones with Sodium Borohydride

✍ Scribed by Konopíková, Marta ;Fišera, L'Ubor ;Prónayová, Nada ;Ertl, Peter

Publisher: John Wiley and Sons
Year: 1993
Tongue: English
Weight: 434 KB
Volume: 1993
Category: Article
ISSN: 0947-3440
DOI: 10.1002/jlac.1993199301168

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The reduction of condensed imides 1 with sodium borohydride proceeds regio‐ and stereoselectively to yield the hydroxylactams 2, 3 and 4. AM1 calculations of the reactants and products reveal that the regiochemistry of the reductions seems to be controlled by both electronic and steric effects. The regio‐ and stereoselectivity of the reductions are dramatically improved by the presence of magnesium perchlorate. This is interpreted in terms of a chelate complex formation between the carbonyl group, isoxazoline oxygen atom and magnesium ion. The presence of p‐toluenesulfonic acid (p‐TsOH) also improves the regioselectivity, but lowers the chemoselectivity.

📜 SIMILAR VOLUMES

“Huisgen Reaction” of Aldonitrones with

“Huisgen Reaction” of Aldonitrones with N-Benzyl Maleimide Leading to Synthesis of 2,3-Diaryl-5-benzyl-2H-3,3a,4,5,6,6a-hexahydropyrrolo [3,4-d]isoxazole-4,6-diones

✍ Jaspreet Kaur; Baldev Singh; Kewal Krishan Singal 📂 Article 📅 2005 🏛 John Wiley and Sons ⚖ 16 KB 👁 1 views

A One-Pot Synthesis of 3-Methyl-5-aryl-4

A One-Pot Synthesis of 3-Methyl-5-aryl-4H-pyrrolo[2,3-d]-isoxazoles.

✍ E. Rajanarendar; G. Mohan; P. Ramesh; D. Karunakar 📂 Article 📅 2006 🏛 John Wiley and Sons ⚖ 20 KB 👁 2 views

A new synthesis of 4,5-dihydro-3,1-benzo

A new synthesis of 4,5-dihydro-3,1-benzoxazepine and 4H-5,6-dihydro-3,1-benzoxazocine derivatives

✍ Yoshihiko Ito; Kazuhiro Kobayashi; Takeo Saegusa 📂 Article 📅 1978 🏛 Elsevier Science 🌐 French ⚖ 195 KB

In a previous paper') we described the generation of o-lithiomethylphenyl isocyanide, which was a versatile reagent for syntheses of indole derivatives. Herein, we wish to report an elaboration of the lithiomethylphenyl isocyanide to lead to heterocycles such as 4,5-dihydro-3,1-benzoxazepine ~~ and

Pyrrole studies: 31. The structures of p

Pyrrole studies: 31. The structures of potentially tautomeric 1,2-dihydro-6H-pyrrolo [3,4-d]pyridazine-1-ones and 1,2,3,4-tetrahydro-6H-pyrrolo [3,4-d]pyridazine-1,4-diones

✍ Sermin Inel; R. Alan Jones; Cemil Ogretir 📂 Article 📅 1984 🏛 Elsevier Science 🌐 French ⚖ 692 KB

Synthesis of New 3-(4-Oxo-4H-chromen-3-y

Synthesis of New 3-(4-Oxo-4H-chromen-3-yl)-3a,6a-dihydropyrrolo [3,4-d]isoxazole-4,6-dione Derivatives by 1,3-Dipolar Cycloaddition Reaction

✍ Zhengfeng Xie; Fangming Liu; Yonghai Hui; Caihong Liu; Yadong Sun 📂 Article 📅 2005 🏛 John Wiley and Sons ⚖ 18 KB 👁 1 views

## Abstract For Abstract see ChemInform Abstract in Full Text.

Synthesis of new 3-(4-oxo-4H-chromen-3-y

Synthesis of new 3-(4-oxo-4H-chromen-3-yl)-3a,6a-dihydropyrrolo[3,4-d]isoxazole-4,6-dione derivatives by 1,3-dipolar cycloaddition reaction

✍ Zhengfeng Xie; Fangming Liu; Yonghai Hui; Caihong Liu; Yadong Sun 📂 Article 📅 2005 🏛 Journal of Heterocyclic Chemistry 🌐 English ⚖ 39 KB

A series of new 3-(4-oxo-4H-chromen-3-yl)-3a,6a-dihydropyrrolo [3,4-d]isoxazole-4,6-dione have been synthesized by the reaction of N-arylmaleimides with nitrile oxide, prepared from α-chloro-4-oxo-4Hchromen-carbaldehyde oximes in situ through 1,3-dipolar cycloaddition reaction. The structures of all