NN Double Bond Research Articles

INDO-SCF and CI calculations on the trans-cis isomerization of azomethane in the ground state and in excited states

INDO-SCF calculations followed by CI calculations with inclusion of multiply, excited configurations were carried out to obtain potential energy curves for isomerization in the ground state and in some low-lying excited states of azomethane. The SCF wavefunctions are analyzed with the aid of newly defined bond characters providing a connection between the chemical concepts of bonds, lone-pairs, etc. and molecular orbital theory. Two different pathways for isomerization are considered and by comparison of the calculated results with experimental data it is concluded that this reaction proceeds in the 1,3 (nπ*) states via rotation of both methyl groups around the NN double bond.

Photochemical [2+2] Cycloaddition between Parallel CC and NN Double Bonds

A [π2s + π2s]-photocyclization between non-activated CC and NN double bonds has been observed for the first time for the rigid molecule (1), which is transformed into a novel cage compound. In other cases this ring closure is precluded by the faster elimination of N2.

1,3‐Anionic Cycloadditions of Organolithium Compounds: An Initial Survey. New synthetic methods (4)

AbstractIn the field of [3 + 2]‐cycloaddition reactions, 1,3‐anionic cycloadditions have now joined 1,3‐dipolar cycloadditions as a second reaction type of major general importance. The cycloaddition in question has been found to occur with 2‐azaallyllithium compounds, allyllithium compounds (with an electron acceptor located on C2), and 1,3‐diphenylpropargyllithium. Compounds with CC, CN, NN, and CS double bonds and those with CC and CN triple bonds were found to be 1,3‐anionophilic. 1,3‐Anionic cycloaddition opens new routes to 1‐aza‐, 1,2‐diaza‐, 1,3‐diaza‐, 1,2,4‐triaza‐, and 1‐thia‐3‐azacyclopentane derivatives, to pyrroles and imidazoles, as well as (and this appears to be of special importance) to cyclopentane derivatives. Currently available data attribute stereospecificity to the 1,3‐anionic cycloadditions, which occupy an interesting intermediate position between 1,3‐dipolar cycloadditions and transition‐metal‐catalyzed cyclizations. A two‐step mechanism has been demonstrated in one case.

Anionic 3 + 2 Cycloaddition of 2‐Azaallyllithium Compounds to CN and NN Double Bonds

Angewandte Chemie International Edition in EnglishVolume 9, Issue 12 p. 960-961 Communication Anionic 3 + 2 Cycloaddition of 2-Azaallyllithium Compounds to CN and NN Double Bonds† Prof. Dr. Thomas Kauffmann, Prof. Dr. Thomas Kauffmann Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorHeike Berg, Heike Berg Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorElisabeth Ludorff, Elisabeth Ludorff Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorAnnegret Woltermann, Corresponding Author Annegret Woltermann Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this author Prof. Dr. Thomas Kauffmann, Prof. Dr. Thomas Kauffmann Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorHeike Berg, Heike Berg Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorElisabeth Ludorff, Elisabeth Ludorff Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this authorAnnegret Woltermann, Corresponding Author Annegret Woltermann Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Organisch-Chemisches Institut der Universität, 44 Münster, Orléansring 23 (Germany)Search for more papers by this author First published: December 1970 https://doi.org/10.1002/anie.197009601Citations: 21 † Organo-lithium and -aluminum Compounds, Part 4. – Part 3: [2]. ‡ This work was supported by the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie. AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume9, Issue12December 1970Pages 960-961 RelatedInformation

The hydrogenation catalyst made from chloroplatinic acid and triethylsilane

An active hydrogenation catalyst is readily made as a suspension by warming chloroplatinic acid with triethylsilane in 95% ethanol. The activity, which is associated with the suspended solid particles, is retained on prolonged storage. The catalyst is more active than Adams catalyst for (a) hydrogenation of simple olefins such as oct-1-ene and cyclohexene, (b) hydrogenation of alkynes, (c) hydrogenation of NN and CN double bonds in azobenzene and benzylidineazine, respectively, (d) reduction of aromatic nitro-compounds to amines, and (e) hydrogenolysis of allyl bromide and chloride. It is less active than Adams catalyst in hydrogenolysis of fluoro- and chlorobenzene, and in hydrogenation of benzene, but is a little better than that catalyst in hydrogenation of dimethylaniline.It is better than the (unsupported) catalyst produced by interaction of chloroplatinic acid and sodium borohydride except in hydrogenolysis of fluoro- and chloro-benzene. The activity of the catalyst from the borohydride in hydrogenation of oct-1-ene has been found to depend on the concentration of hydrochloric acid, being greatest in the presence of a very small amount of acid.Catalysts made by reduction of platinum oxide with triethylsilane or of potassium chloroplatinite with ethanol are better than Adams catalyst in some reactions.