ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Photoenolisation. X.Parts VIII and IX, see [2 l, m].. An ab initio SCF-CI study (1979)

Sevin, A. ; Bigot, B. ; Pfau, M.

New York, NY : Wiley-Blackwell

Helvetica Chimica Acta 62 (1979), S. 699-710

add to mindlist on the mindlist

Details

ISSN: 0018-019X

Keywords: Chemistry ; Organic Chemistry

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Notes: The processes involved in photoenolisations are theoretically simulated by an ab initio SCF-CI method, using cis-2-butenal as a prototype structure. The prominent role of the hydroxyl group conformation in the resulting transient (2a) is emphasized; its rotation ‘out of the reaction site’ allows the next reaction paths to proceed exothermally. The equilibration of the different types of twisted biradicals in the triplet manifold, which only involves a low energy barrier, is thus possible, populating in quite equal weights the precursors of both E- and Z-dienols. In the singlet state, the formation of the Z-isomer is expected to be kinetically dominant. An examination of the role of the substituents suggests that, in related systems, the steric crowding induces important structural relaxation of the dienol geometries.

Additional Material: 5 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/hlca.19790620309

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Etude par Spectrométrie de Masse d'une Série de Phényl-1 Naphtalènes Substitués et des Dihydro-1,4 Naphtols-1 Correspondants (1977)

Pfau, Michel ; Heindel, Ned D. ; Gülaçar, Fazil O. ; [et al.]

Chichester : Wiley-Blackwell

Biological Mass Spectrometry 12 (1977), S. 644-650

add to mindlist on the mindlist

Details

ISSN: 0030-493X

Keywords: Chemistry ; Analytical Chemistry and Spectroscopy

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Chemistry and Pharmacology

Description / Table of Contents: The 70 eV electron impact mass spectra of a series of substituted 1-phenylnaphthalenes and their corresponding 1,4-dihydro-1-naphthols have been studied. Plausible fragmentation modes which account for the formation of all the major ions are proposed. An interesting hydrogen transfer reaction, leading to major fragments through the elimination of methanol, seems to proceed via an 8-membered transition state mechanism.

Notes: Une étude par spectrométrie de masse d'une série de phényl;-1 naphtalenes substitués et des dihydro-1,4napthols-1 correspondants permet de proposer des modes de formation plausibles pour tous les ions importants. L'élimination de méthanol, qui aboutit à des ions majeurs, fait probablement intervenir le transfert d'un atome d'hydrogène par un état de transition à huit atomes.

Additional Material: 3 Tab.