1,3‐Anionische Cycloadditionen, XIII. endo‐exo ‐Isomere Cycloaddukte aus trans , trans ‐1,3‐Diphenyl‐2‐azaallyllithium und Acenaphthylen

Abstract

Eingegangen am 12. Mai 1976 trans,trans-l,3-Diphenyl-2-azaallyllithium (1) cycloaddiert sich bei 0 oder -70°C unter Retention an Acenaphthylen zu einem Gemisch von N-Lithio-syn-und N-Lithio-anti-7,9-diphenyl-7,8,9,9a-tetrahydro-6bH-acenaphtho[1,2-c]pyrrol (3a, 4a, R = Li) (ca. 1 : 1). Das syn-Isomere (endo-Cycloaddukt) lagert sich bei + 35. C in das anti-Isomere (exo-Cycloaddukt) um. 1,lAnionic Cycloadditions, XIII'' endo-exo-Isomeric Cycloadducts of trans~ranu-1,3-Dipbenyl-2-azaaUyUithium and Acenaphthylenetrans,trans-1,3-Diphenyl-2-azaallyllithium adds at 0 or -70°C to acenaphthylene with retention of configuration to give a mixture of N-lithio-syn-and N-lithio-anti-7,9-diphenyl-7,8,9,9a-tetrahydro-6bH-acenaphtho[l,2-c]pyrrole (3a, 4% R = Li) (ca. 1 : 1). The syn-isomer (endo-cycloadduct) rearranges to the anti-isomer (em-cycloadduct) at + 35°C.

Use of Group 4 Bis(sulfonamido) Complexes in the Intramolecular Hydroamination of Alkynes and Allenes.

“…13 A solution of N-4-methyl-benzyliden-4-methyl-benzylamine (415 mg, 1.86 mmol) in THF (20 mL) was cooled to -78 °C and treated with LDA [prepared from n-BuLi (1.6 M in n-hexane; 1.0 mL, 2.1 mmol) and diisopropylamine (0.3 mL, 2.1 mmol) in THF ( 5mL)] according to the literature. 14 The resulting deep red solution was stirred for 2 h after dienyl-1-amine (227 mg, 65%) as a pale yellow oil with a purity of 98% by NMR.…”

Information-analytical system of chemical technology processes modeling by the use of parallel calculations

“…In the series of Schiff bases, N-benzylidene benzylamine has an important place and has wide application in practice. In particular, N-benzylidene benzylamine is known as an indicator for the quantitative determination of lithium-organic compounds by titrimetric method [10][11][12]. N-benzylidene benzylamine is used as an initial compound for the synthesis of a number of heterocycles.…”

Perspectives on Intermolecular Azomethine Ylide [3+2] Cycloadditions with Non-Electrophilic Olefins

“…However, even when counting with these additional driving forces, the cycloaddition between acenaphthylene and a model 2-aza-allyl anion was found to be reversible and poorly stereoselective (Scheme 3, b). 29 Both facts are suggestive of the adverse thermodynamics and low-energy step-wise pathways that may be operating in 2-aza-allyl lithium cycloadditions.…”

“…In fact, the cycloreversion has been documented in several of the reports that have been discussed in the sections above. 27b, 29,40 Scheme 8 Fundamental difference in thermodynamic driving force between reactions mediated by transition metals and main-group metals.…”