Deuterium-Labeled Benzyladenine: Synthesis and Application as a Surrogate

Intramolecular Metal‐Free N−N Bond Formation with Heteroaromatic Amines: Mild Access to Fused‐Triazapentalene Derivatives

“…The amide anion A can react with iodine(III) to form the hypervalent iodine intermediate B and may then evolve according to two pathways (Scheme ). Pathway 1 could be a two‐step mechanism involving a nitrenium ion intermediate C , a species favored in recent literature but the formation and stability of which could be unfavorable in the present study because of the presence of the electron‐poor azine moiety. On the other hand, pathway 2 only involves a one‐step process, with the direct attack by the pyrazole's nitrogen atom at the intermediate B stage which, this time, will be promoted by the presence of the azine, making the iodine‐bonded nitrogen more electrophilic …”

Total synthesis of [ 15 N]-labelled C6-substituted purines from [ 15 N]-formamide—easy preparation of isotopically labelled cytokinins and derivatives

“…Generally, CKs labelled with deuterium or 13 C nuclide are most frequently prepared [16,20,21,23–25]. For 15 N labelling, to the best of our knowledge, for aromatic cytokinins only the preparation of [ 15 N 1 ]-BAP has been described in the literature [17,18].…”

“…The prevalence of approaches that use deuterium or 13 C nuclide to prepare isotopically labelled CKs is reasonable. Deuterium labelling is relatively inexpensive and can be accomplished using deuterated catalytic reduction systems [23,25] or catalysed hydrogen-deuterium exchange [16]. The 13 C nuclide could easily be integrated by using 13 C reagents [20,23,24].…”

“…Additionally, [ 2 H 4 ]-BAP can be obtained by a hydrogen–deuterium exchange reaction catalysed by palladium on a carbon-ethylene diamine complex [Pd/C(en)]. In this method, the hydrogen–deuterium exchange occurs most frequently at C2, C8 (94%) and side chain carbon positions (97%) [16].…”

“…Among ARCKs, the 2 H and 15 N isotopologues of 6-benzylaminopurine (BAP) have already been prepared. Deuterium can be incorporated with a catalysed hydrogen–deuterium exchange reaction [16]. A reaction between 6-chloropurine and the corresponding isotopically labelled [ 15 N 1 ] amine can be used to achieve a more stable [ 15 N 1 ]-BAP [17,18].…”