Photochemical Cycloaddition Reactions Research Articles

Chemistry of exciplexes 11: Photocycloaddition of 1,3-cyclohexadiene to polynuclear aromatic hydrocarbons

Extending our investigations on the photochemical reactions between benzenoid aromatic hydrocarbons and conjugated polyunsaturated olefins to the higher arenes, we describe the pericyclic reactivity evidenced in the photochemical cycloaddition reactions of anthracene, tetracene, benz(a)anthracene, dibenz(a,c)anthracene, dibenz(a,h)anthracene, dibenz(a,j)anthracene and pentaphene with 1,3-cyclohexadiene. The divergent reactivities of these arenes is not explicable in terms of Woodward-Hoffmann or derivative theories. We attribute the proclivities of these systems to engage in pericyclic cycloaddition reactions, and in particular the failure of dibenz(a,h)anthracene and pentaphene to from “allowed” 4π s + 4π s meso cycloadducts, to a requirement for the preservation of “essential symmetry” about the reactive positions, wherein the local nodal structure of the reactants must correlate with that of the products for a pericyclic process to be energetically competitive with other modes of deactivation of the arene excited state. Applicability of this theory in thermal processes is also considered.

Molecular complexes of maleic anhydride with acetone and benzene

Concentration and temperature-dependent NMR chemical shifts for maleic anhydride in acetone and benzene solution are interpreted in terms of equilibria between monomers and solvent-solute molecular complexes. Calorimetric heats of dilution and heats of solution give thermodynamic parameters that agree with those determined in the NMR experiments. The thermodynamic parameters obtained are similar for both systems, and it is possible that the previously established role of a ground state complex in the benzene-maleic anhydride photochemical cycloaddition reaction can be extended to the acetone-maleic anhydride photocycloaddition.

ChemInform Abstract: PHOTOCHEMICAL CYCLOADDITION REACTIONS OF α,β‐UNSATURATED LACTONES WITH OLEFINS, AND APPLICATION TO SYNTHESIS OF NATURAL PRODUCTS

AbstractDurch photochemische Cycloaddition können aus den Lactonen (I) und den entsprechenden ungesättigten Verbindungen die Addukte (II), (III), (IV) und (V) gewonnen werden [(IId), (IIId) und (V) als Stereoisomerengemische].

Photochemical Cycloaddition Reactions of α,β-Unsaturated Lactones with Olefins, and Application to Synthesis of Natural Products

Abstract The photochemical cycloaddition reactions of five- and six-membered α,β-unsaturated lactone derivatives with unsaturated substrates (ethylene, acetylene, 1,1-dimethoxyethylene etc.) have been studied. The parent α,β-unsaturated lactone (γ-crotonolactone) and the β-,γ-, or δ-alkyl substituted derivatives add to ethylene and acetylene in the acetone solutions and to 1,1-dimethoxyethylene in the benzene solutions in so good yields as to utilize them practically for synthesis. α-Phenyl-γ-crotonolactone and β-phenyl-γ-crotonolactone also add to ethylene and acetylene, whereas, α-methyl, β-hydroxy, and β-methoxy derivatives do not. As the synthetic applications of the reactions, the synthesis of (±)-grandisol has been achieved, and the synthetic approach to (±)-canadensolide has also been described.

Synthesis of Heterocycles via Cycloadditions to 1-Azirines

The wide applicability of 1-azirines as reagents for the syntheses of many well-known and novel heterocyclic systems is discussed in this article. Although most work has been concentrated on thermal and photochemical cycloaddition reactions of 1-azirines, reactions which proceed via C-N-, N =C-, or C-C-bond cleavage are included. Also, reactions which proceed formally via cycloaddition but give rise to open-chain products are also described. 1. Carbenoid Additions 2. 1,3-Dipolar Reactions 3. Diels-Alder Reactions 4. Ketenes and Ketenimine Additions 5. Isocyanate Additions 6. Miscellaneous Additions 7. Photochemical Cycloadditions

Synthetic Photochemistry. I. The Cycloaddition Reaction of Methyl Acetopyruvate with Olefins

Abstract The photochemical cycloaddition reaction of methyl acetopyruvate, an unsymmetrical β-diketone, with olefins afforded the single 1 : 1 molar adducts in good yields. A ready method of the cyclization of the adducts to the β-methoxycarbonyl-Δα,β-cyclohexenones has preparative values.

Synthesis of novel bicyclic prostaglandins by photochemical cycloaddition reactions

Light-induced addition reactions of cyclopentenone derivatives with ethylene, followed by elaboration of the alkyl chains at positions 8 and 12, give bicyclic prostanoic acid analogues belonging to the prostaglandin E2 and F2α series. Cycloaddition of ethylene to prostaglandin A2 methyl ester yields simultaneously the α- and β-cyclo-adducts. Photochemical addition of allene to prostaglandin A2 derivatives affords mixtures of photoadducts which vary with the nature of the functional group at position 15, thus illustrating the versatility of these photocondensation reactions.

Photochemical cycloaddition reactions. II. Dimerization and cycloadduct formation of some seven-membered carbocycles

Photochemical cycloaddition reactions. II. Dimerization and cycloadduct formation of some seven-membered carbocycles

Photochemical Cycloaddition Reactions of Enones to Alkenes; Synthetic Applications

This review discusses the structural variations in the products of photochemical cycloadditions of olefins to enones, and cites the various ways in which the reaction may be synthetically useful. Die photochemische Cycloaddition von konjugierten Enonen an Alkene stellt in vielen Fällen eine präparativ brauchbare Methode zur Herstellung von sonst nur schwer zugänglichen Cyclobutan-Derivaten und ihren Folgeprodukten dar. In dieser Übersicht werden nach einer allgemeinen Besprechung der Reaktion die Strukturmöglichkeiten der Cycloadditionsprodukte und die synthetische Anwendbarkeit dieser Additionsreaktion anhand von Beispielen aufgezeigt.

Photochemical cycloaddition reactions involving carbostyrils

Photochemical cycloaddition reactions involving carbostyrils

Photochemical Cycloaddition Reactions with Norbornene

Photochemical Cycloaddition Reactions with Norbornene

Some photochemical cycloaddition reactions of coumarin

Some photochemical cycloaddition reactions of coumarin

A Novel Photochemical Cycloaddition Reaction of Benzene

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA Novel Photochemical Cycloaddition Reaction of BenzeneR. Srinivasan and K. A. HillCite this: J. Am. Chem. Soc. 1965, 87, 20, 4653–4654Publication Date (Print):October 1, 1965Publication History Published online1 May 2002Published inissue 1 October 1965https://doi.org/10.1021/ja00948a052RIGHTS & PERMISSIONSArticle Views122Altmetric-Citations14LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (288 KB) Get e-Alerts Get e-Alerts