✦ LIBER ✦

Some novel aspects of regioselectivity in 1,3 dipolar cycloadditions of 4h-1-benzopyran-4-thione

✍ Scribed by Arpan K. Baruah; Dipak Prajapati; Jagir Sandhu

Publisher: Elsevier Science
Year: 1988
Tongue: French
Weight: 326 KB
Volume: 44
Category: Article
ISSN: 0040-4020
DOI: 10.1016/s0040-4020(01)89803-3

No coin nor oath required. For personal study only.

✦ Synopsis

4H-1-Benzopyran-4-thione (1) reacted smoothly with nitrilimines (3a-e) to afford regioselective cycloadducts (4a-e) in good yields. In contrast, benzunitrile oxide (6) and aldonitrones (7a-d) reacted preferentially at the thione function. The unstable cycloadduct (8) or ( 9) ruptured to give as isolable products chromone (10) and phenyl isothiocyanate (11) and the thioamides (12a -d). This indirectly proves the site of attack of the dipole at the thione group.

📜 SIMILAR VOLUMES

Some novel aspects of regioselectivity i

Some novel aspects of regioselectivity in 1,3 dipolar cycloadditions of 4H-1-benzopyran-4-thione: J.S. Sandhu, A.K. Baruah and D. Prajapati Tetrahedron, vol. 44, no. 19, pp. 6137 to 6142, 1988

📂 Article 📅 1989 🏛 Elsevier Science 🌐 French ⚖ 33 KB

Synthesis of Substituted Hydroxyspiro([1

Synthesis of Substituted Hydroxyspiro([1]benzopyran-2,4′(1′H)pyrimidine)-2′(3′H)thiones and Hydroxyspiro([1]benzopyran-2,4′(1′H)pyrimidin)-2′(3′H)ones.

✍ S. I. Filimonov; E. I. Vaganova 📂 Article 📅 2003 🏛 John Wiley and Sons ⚖ 88 KB 👁 1 views

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

ChemInform Abstract: A One-Pot Synthesis

ChemInform Abstract: A One-Pot Synthesis and 1,3-Dipolar Cycloaddition of [1,2]Dithiolo[4,3-b]indole-3(4H)-thiones.

✍ Lidia S. Konstantinova; Kirill A. Lysov; Stanislav A. Amelichev; Natalia V. Obru 📂 Article 📅 2009 🏛 John Wiley and Sons ⚖ 31 KB 👁 1 views

ChemInform Abstract: 1,3-Dipolar Cycload

ChemInform Abstract: 1,3-Dipolar Cycloadditions of a Carbonyl-Ylide with 1,3-Thiazole-5(4H)- thiones and Thioketones.

✍ K.-R. MEIER; A. LINDEN; G. MLOSTON; H. HEIMGARTNER 📂 Article 📅 2010 🏛 John Wiley and Sons ⚖ 31 KB 👁 2 views

1,3-Dipolar Cycloaddition of Ethyl Propi

1,3-Dipolar Cycloaddition of Ethyl Propiolate to 4,4-Dimethyl-4,5-dihydro-1,2-dithiolo[5,4-c]quinoline-1-thiones.

✍ S. M. Medvedeva; Kh. S. Shikhaliev; G. I. Ermolova; A. S. Solov'ev; G. V. Shatal 📂 Article 📅 2003 🏛 John Wiley and Sons ⚖ 123 KB 👁 1 views

Deactivation of the lowest triplet state

Deactivation of the lowest triplet state of 4-H- 1 -benzopyran-4-thione in different solvents

✍ Marek Sikorski; Włodzimierz Augustyniak; Igor V. Khmelinski; Valery V. Korolev; 📂 Article 📅 1993 🏛 Elsevier Science 🌐 English ⚖ 488 KB

Investigation of 4-H-I-benzopyran-4-thione (BPT) in its triplet state was performed in a flash photolysis system. The kinetics of phosphorescence and transient triplet-triplet absorption decay of BPT were measured in deoxygenated solutions. The studies were made with both protic and aprotic solution