Reactions of palladium(II) chloride with aziridine rings. Catalytic rearrangement of N-carbethoxy-8-azabicyclo[5.1.0]oct-3-ene to N-carbethoxynortropidine

Wiger, George; Rettig, Michael F.

doi:10.1021/ja00430a027

Cited by 27 publications

(2 citation statements)

References 10 publications

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“…17 A somewhat more complex result was obtained by FVP of the diazomethane adduct 8 at 475 ЊC. 17 A somewhat more complex result was obtained by FVP of the diazomethane adduct 8 at 475 ЊC.…”

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Pyrolysis of tricyclic cyclobutane-fused sulfolanes as a route to cis-1,2-divinyl compounds and their Cope-derived products

Aitken¹,

Cadogan²,

Gosney³

et al. 1999

J. Chem. Soc., Perkin Trans. 1

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Functionalisation of the double bond of 3-thiabicyclo[3.2.0]hept-6-ene 3, readily formed by hydrolysis of the [2ϩ2] cycloadduct 1 of 3-sulfolene and maleic anhydride followed by oxidative bis-decarboxylation, gives tricyclic sulfones 5-7 and 9 with the bicyclo[3.3.0.0 2,4 ] skeleton. FVP of 3 results in stereospecific extrusion of SO 2 to give Z-hexa-1,3,5-triene which undergoes electrocylisation to give cyclohexa-1,3-diene while reaction of 3 with LiAlH 4 results in non-stereospecific extrusion to give Z-and E-hexa-1,3,5-triene. Upon FVP the tricyclic sulfones 5-7 and 9 lose SO 2 to give 7-membered ring products 16-19 by Cope rearrangement of the initially formed cis-1,2-divinyl intermediates 15. The 1,3-dipolar cycloaddition of nitrile oxides and a nitrone to the double bond of 3 gives tricyclic sulfones with the tricyclo[5.3.0.0 2,6 ] skeleton and a wider variety of these can be prepared by conventional reactions of 1. Upon FVP these lose SO 2 to give stable cis-1,2-divinyl compounds 23, 24, 37-40 and 41-44. The Diels-Alder adducts 48 and 49 have been prepared from 3 and these behave differently upon FVP, losing SO 2 and butadiene to give tetrasubstituted benzenes, in the latter case by way of an unexpected tetracyclic intermediate.Thermal extrusion of SO 2 from cyclic compounds has been widely used as a synthetic method and often allows access to products which would be difficult to obtain by other methods. 1 The pyrolysis of functionalised sulfolenes and sulfolanes is of particular importance and has found numerous applications. 2 Although there have been a few studies on cyclopropane-fused sulfolanes and their heterocyclic analogues, there were no examples of the corresponding method being applied to cyclobutane-fused sulfolanes prior to our work in the area. The general approach, summarised in Scheme 1, may be used to access a wide range of cis-1,2-divinyl compounds and, depending upon the ring size involved, the products derived from their Cope rearrangement. We now present full details of the synthesis of cyclobutane-fused sulfolanes with an additional 3-, 5-or 6-membered fused ring and their reactivity under flash vacuum pyrolysis (FVP) conditions. 3

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