Über hochpolymere Verbindungen. 22. Mitteilung. Über die Konstitution des Poly‐indens

Abstract

Die Kondensation der Aldehyde mit o-Kresotinsaure erfolgte nach D.R.P. 23402F). Die Leukoverbindung wurde mit Nitrosylschwefelsiiure zum Farbstoff oxydiert.Die nachchromierten Farbungen zeichneten sich durch ausserordentliche Reinheit in der Nuance und durch gute Waschechtheit aus.Farbstoff aus 2,6-Dichlor-benzaldehyd : Absorptionsspektrum in Natronlauge I. = 597,B ,, Schwefelsaure 1 = 536,s , ,, Schwefelsaure + Borsaure 1 = 535,8 undeutlich. Farbstoff aus 2,4-Dichlor-benzaldehyd : Absorptionsspektrum in Natronlauge 3. = 593,O 3, ,, Schwefelsaure 1 = 521,5 Der Farbstoff aus 2,4-Dichlor-benzaldehyd ist, wie schon das Patent von Geigy sagt, sehr farbschwach. Die Fiirbung ist truber und viel griiner als jene des Eriochromakurols von Geigy. 0rg.-Techn. Laboratorium, Eidg. Techn. Hochschule in Ziirich. Uber hochpolymere Verbindungen. Uber die Konstitution des Poly-indens von € I . Staudinger, A. A. Ashdown3), M. Brunner4), € I . A. Bruson5) und S. WehrlP). (23. VIII. 29.)

The Fractionation of High-Polymeric Substances.

“…In 1929, Staudinger (272) reported the fractionation of polyanethole with ethyl ether, and in another paper (269) that of polyindene with petroleum ether or ethyl ether; the ether-insoluble portion was extracted with boiling cyclohexane, and this solution fractionated by precipitation with methanol.…”

ADMET: The Future Revealed

“…Tacticity represents one of the most fundamental concepts in polymer chemistry. 35 One has only to compare the properties of syndiotactic, isotactic, and atactic polypropylene to understand the important consequences that controlling (or not controlling) the tacticity of a polymer has on the properties of a material. 36 The result of the creation of these materials was the Nobel prize awarded jointly to Karl Ziegler and Giulio Natta in 1963, in part for the creation of polypropylene.…”

Origins of stereoselectivity in radical additions: reactions of alkenes and radicals bearing oxazolidine and thiazolidine amide groups

“…Crystal data: 2, C10Hi5NO3S, M = 229.30, monoclinic, space group P2U a = 8.137 (1) A, b = 9.635 (1) A, c = 7.826 (1) A, 0 = 105.07 (1)°, V = 592.5 (2) A3, Z = 2, = 1.285 g cm"3, M(Cu Ka) = 23.0 cm"1; 4b, C12H2iN02, M = 211.31, orthorhombic, space group P212121, a = II. 137 (1) A, b = 15.598 (1) A, c = 7.221 (1) A, v = 1254.4 (4) A3, Z = 4, lAaUaj = 1.119 g cm'1, m(Cu Ka) = 5.7 cm"1; 4c, C14H17N02, orthorhombic, space group F212121, a = 10.867 (1) A, b = 19.153 (2) A, c = 6.277 (1) A, V= 1306.5 (5) A3, Z = 4, = 1.176 g cm"3, M(Cu Ka) = 5.9 cm"1; 5c, C26H30N2O4, M = 434.54, orthorhombic, space group F2,2,2" a = 11.461 (1) A, b = 35.216 (3) A, c = 6.070 (1) A, V = 2449.9 (8) A3, Z = 4, = 1.176 g cm"3, m(Cu Ka) = 6.1 cm"1; 12b, C23H36N202S, M = 406.62, monoclinic, space group P2\, a = 9.548 (1) A, b = 13.731 (1) A, c = 9.472 (1) A,/3 = 110.47 (1)°, V= 1163.4 (4) A3, Z = 2, Dak* = 1.155 g cm"3, m(Cu Ka) = 13.4 cm"1; 15c, C43H5iBrCl3N306, M = 892.17, monoclinic, space group P2U a = 11.527 (1) A, b = 19.657 (2) A, c = 9.894 (1) A, 6 = 96.19 (1)°, V= 2228.8 (7) A3, Z = 2, Dalai = 1-329 g cm"3, m(Cu Ka) = 33.4 cm"1.…”

“…Hart,9 Guindon,10 Giese,11 and Curran12 have examined substrate-controlled p acyclic selectivity in systems where 1,3 allylic strain is thought to orient the facial bias of the radical reaction, Figure 1. Reaction of the radical on the face bearing the small (S) substituent is preferred to reaction on the radical face bearing the large (L) group.…”