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Zustand: Fair. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. In fair condition, suitable as a study copy. No dust jacket. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,1250grams, ISBN:3527284893.

Zustand: Gut. 440 S.* mit zahlr. Abb.s/w, Text engl. 8° Softcover, ausgeschiedenes Exemplar einer Universitätsbibliothek, gestempelt im Vorsatz und div., Aufkleber auf Buchrücken (entfernt), stärkere Gebrauchsspuren an Ecken und Kanten, Schnitt angestaubt, einige Seiten innen am Block verstärkt (in sich alles fest), innen gutes Exemplar N5 Sprache: Englisch Gewicht in Gramm: 750.

Zustand: New. In.

Paperback. Zustand: Brand New. 368 pages. 8.27x5.83x0.83 inches. In Stock.

Taschenbuch. Zustand: Neu. Druck auf Anfrage Neuware - Printed after ordering - In the tricyclooctanone approach to polyquinane syntheses[ll the photochemical rearrangement of bicyclo[2.2.2]octenone, 1a 2a,[2J has been the initial key reaction providing tricyclo 2 [3.3.0.0 ' S]octan-3-one as a chiral building block.[3-SJ This reaction - an oxadi-n-methane (ODPM) process - and the 1,3-acyl shift (AS) forming the cyclobutanone 3 are quite generally the characteristic re arrangement paths undergone by ~,~-unsaturated ketones (~,~-UKs) upon triplet sensitization and direct excitation with ultraviolet light, respectively. R' R' hv hv R~O ~ ~ (sens) WO ~ R ONR R 1a-c 2a-c 3a-c a R=R'=H b R = CH , R'= H 3 c R = R'= CH 3 As a polyvalent building block, the enantiomers of which are readily accessible from cheap bulk chemicals such as benzene and its derivatives, the parent system 1a and three younger generations of its class (Sections 3.1. - 3.4.) have no equal among synthetically useful photochemical rearrangements. 2. THE PHOTOCHEMISTRY OF ~,~-UNSATURATED KETONES The literature dealing with the spectroscopy and photo chemistry of ~,~-UKs has been exhaustively and critically reviewed around 1975 by Dauben et al.[6l and Houk,[7J and in 1980 by Schuster.[SlI1 The 1,3-AS was first observed on direct excitation of 1) For more recent papers on i3,~-UK photochemistry see [9-24]. 64 ~ R' hv ~o hv .,.

32. Zustand: Wie neu. Sprache: Deutsch.