120692-81-1Relevant articles and documents
Intramolecular Amido Transfer Leading to Structurally Diverse Nitrogen-Containing Macrocycles
Kim, Heejeong,Chang, Sukbok
, p. 3344 - 3348 (2017/03/17)
Reported herein is the development of rhodium-catalyzed intramolecular amido transfer as an efficient route to nitrogen-containing macrocycles starting from acetophenone ketoximes tethered with either aryl or alkyl azides. Facile generation of rhodacycles and metal imido intermediates was the key to success in this mechanistic scaffold to represent the first example of an intramolecular inner-sphere C?H amination. While substrates bearing aryl azides underwent a monomeric ring formation in high yields, a dimeric double cyclization took place exclusively with alkyl-azide-tethered ketoximes, thus affording up to 36-membered azamacrocyclic products.
Photochemical generation of iminoquinone methides by 1,4-hydrogen migration in derivatives of o-tolylnitrene
Bucher, Goetz
, p. 2447 - 2462 (2007/10/03)
The photochemistry of a series of derivatives of o-tolyl azide, bearing a variety of substituents in the benzylic positions, has been investigated using matrix isolation spectroscopy and density functional calculations. It has been found that introduction of any substituent possessing a lone pair (i.e., R = Br, Cl, MeO, Me2N) allows a 1,4-hydrogen shift to take place, yielding iminoquinone methides. Additional methyl groups in the benzylic position, however, do not promote a photochemical conversion into iminoquinone methides. If the benzylic substituent itself is part of a ring system, the size of this ring plays an important role. Thus, 2-methyl-8-nitrenote-trahydroisoquinoline rearranges very easily, whereas 4-nitrenophthalan does not give the reaction. Density functional calculations [B3LYP/6-31G(d)] have been used to gain an understanding of the reaction. It has been found that the activation energies depend strongly on the nature of the substituent, being lowest if R = NMe2. Incorporation of the benzylic substituent into a ring reduces the flexibility of the system and results in significantly raised barriers.
