Reference

Gas-phase reactions of 1,4-benzodioxan, 2,3-dihydrobenzofuran, and 2,3-benzofuran with hydroxyl radicals and ozone

Gas-phase reactions of 1,4-benzodioxan, 2,3-dihydrobenzofuran, and 2,3-benzofuran with hydroxyl radicals and ozone. Atkinson, Roger; Arey, Janet; Tuazon, Ernesto C.; Aschmann, Sara M. (Statewide Air Pollut. Res. Cent., Univ. California, Riverside, CA 92521, USA). Int. J. Chem. Kinet., 24(4), 345-58 (English) 1992. CODEN: IJCKBO. ISSN: 0538-8066. DOCUMENT TYPE: Journal CA Section: 22 (Physical Organic Chemistry) The kinetics of the gas-phase reactions of 1,4-benzodioxan, 2,3-dihydrobenzofuran, and 2,3-benzofuran with OH radicals and O3 have been studied at 298 ± 2 K and atm.There are some reagents with their cas registry numbers 3352-57-6 and 493-09-4 are used in this study. pressure of air and the products have also been investigated. 1,4-Benzodioxan and 2,3-dihydrobenzofuran were chosen as volatile model compds. for dibenzo-p-dioxin and dibenzofuran, resp. The rate consts., or upper limits thereof, for the O3 reactions were (in cm3 mol.-1 s-1 units): 1,4-benzodioxan, <1.2 ′ 10-20; 2,3-dihydrobenzofuran, <1 ′ 10-19; and 2,3-benzofuran, (1.83-0.21) ′ 10-18. Using a relative rate method, the rate consts. for the OH radical reactions (in cm3 mol.-1 s-1 units) were: 1,4-dibenzodioxan, (2.52±0.38) ′ 10-11; 2,3-dihydrobenzofuran, (3.66 ± 0.56) ′ 10-11; and 2,3-dibenzofuran, (3.73 ± 0.74) ′ 10-11. Salicylaldehyde was obsd. as a product of the OH radical-initiated and O3 reactions of 2,3-benzofuran, with measured formation yields of 0.26 ± 0.05 and 0.13 ± 0.07, resp. .

Synthesis in the field of podophyllotoxin and related analogues: Part XII - Synthesis of benzodioxan analogue of didemethoxy-b-apopicropodophyllin

Shashikanth, S.; Hegde, Ganesh L. (Department of Studies in Chemistry, University of Mysore, Mysore 570 006, India). Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 43B(8), 1713-1720 (English) 2004 National Institute of Science Communication. CODEN: IJSBDB. ISSN: 0376-4699. DOCUMENT TYPE: Journal CA Section: 26 (Biomolecules and Their Synthetic Analogs) The benzodioxan analog of didemethoxy-b-apopicropodophyllin was synthesized starting from 4-methoxybenzoic acid. On Stobbe condensation of 2,3-dihydro-benzo[1,4]dioxin-6-yl-(4-methoxyphenyl)methanone with di-Et succinate followed by redn. with sodium amalgam yields I. Cyclization of I with PPA furnishes tetralone ester. Formylation of the ester with Et formate and sodium hydride affords II, which on sodium borohydride redn. followed by alk. hydrolysis and finally on treatment with p-toluenesulfonyl chloride gives III.Except for chemicals metioned above, 493-09-4 and 823219-65-4 are also used. .