Formation of Four-Membered Rings Using the Intramolecular Wittig Reaction: Convenient Generation of Functionalised Butadienes

Aitken, R. A.; Balkovich, Mark E.; Bestmann, Hans Jürgen; Clem, Oliver; Gibson, S. E.; Röder, Thomas

doi:10.1055/s-1999-2811

Cited by 8 publications

(2 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although domino approaches to alkenylnaphthalenes 4 and substituted 1,3-dienes 5 have also been described, the majority of work has focused on ylides of general structure 1 or 2 (Scheme 1). Thermal extrusion of…”

Section: Introductionmentioning

confidence: 99%

New Gas-Phase Domino Processes Leading to Benzopyranones and Benzofurans

Aitken

Chang²

2016

HETEROCYCLES

View full text Add to dashboard Cite

-A new domino approach to flavones by gas phase pyrolysis of -dioxophosphonium ylides containing a 2-methoxyphenyl group is frustrated by unexpected and novel decarbonylation of the intermediate flavon-3-yl radical leading to 2-phenylbenzofuran. Alternative approaches based on dioxolane protection of one carbonyl, or selective elimination in '-dioxo or -oxo-'-thioxo ylides were not successful, but pyrolysis of a -oxo-'-phenylimino ylide did give the required domino reaction leading to a protected benzopyranone in moderate yield.

show abstract

Section: Introductionmentioning

confidence: 99%

New Gas-Phase Domino Processes Leading to Benzopyranones and Benzofurans

Aitken

Chang²

2016

HETEROCYCLES

View full text Add to dashboard Cite

show abstract

“…[1,2] In an attempt to extend this chemistry, we have examined the pyrolysis of several new types of stabilised ylides and in this paper we describe the Michael addition of ketone-and ester-stabilised ylides to vinyl ketones to give β,δЈ-dioxo ylides [3] and their subsequent pyrolytic behaviour. [4] …”

Section: Introductionmentioning

confidence: 99%

Synthesis and Pyrolytic and Kinetic Behaviour of β,δ′‐Dioxo‐Stabilised Phosphorus Ylides: Convenient Preparation of γ,δ‐Alkynyl Ketones and 2,3‐Functionalised Butadienes

et al. 2003

Self Cite

View full text Add to dashboard Cite

Both ketone‐ and ester‐stabilised phosphorus ylides undergo Michael addition to vinyl ketones to give the β,δ′‐dioxo ylides 3 and 5, respectively, although in the latter case careful temperature control is required to avoid an undesired side‐reaction. Under conditions of flash vacuum pyrolysis at 650 °C the ylides 3 generally undergo Ph3PO extrusion to afford the γ,δ‐alkynyl ketones 14, although these are found to partly undergo a secondary fragmentation. In contrast, the ylides 5 react under the same conditions to give the synthetically useful 1,3‐dienes 20 by way of cyclobutenes. Rate constants for the reaction of selected ylides 3 and 5 are reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

show abstract