Synthesis of 7‐Azaindole Amidated Derivatives: An Efficient Usage of Acyl Azides as the Nitrogen Source

Abstract

The dual behaviour of acyl azides in transition-metal-catalyzed direct CÀH amidation is investigated. Variously substituted acyl azides reacted smoothly with 7-azaindoles providing a diversity of CÀC or CÀN 7-azaindole amidated derivatives. This amidation reaction shows an excellent controllability, which is believed to be dependent on catalyst system.

RuV‐Acylimido Intermediate in [RuIV(Por)Cl2]‐Catalyzed C–N Bond Formation: Spectroscopic Characterization, Reactivity, and Catalytic Reactions

“…Thed evelopment of metal-catalyzed acylnitrene transfer (MCAT) to organic substrates,compared with stoichiometric analogues by L n Mn V (N)/(CF 3 CO) 2 Oo rL n Mn V (N)/RCO-Cl, [3, 4, 26a, 30a,43] has met with formidable challenges [5,6] until recently; [7][8][9][10][11][12][13][14][15][16] the overwhelming majority of the recent examples deal with CÀHa mination and are based on substrates bearing directing groups (DGs) that can bind to the metal center. Examples on the use of MCATs for other reactions such as alkene aziridination are sparse.T he [Ru IV (Por)Cl 2 ]/ N 3 COR method is applicable to various MCATr eactions including alkene aziridination described in this work and to substrates without DGs.…”

“…Oxazoline products were obtained by extending the [Ru IV (TDCPP)Cl 2 ](3 mol %)/N 3 COR method to the following types of alkenes:i )aryl alkenes 2j-q devoid of strongly [5][6][7][8][9][10][11][12][13][14][15] B) proposed Ru V (O) intermediatesi n[Ru IV (Por)Cl 2 ]-catalyzed oxygen atom transfer reactions. [20] electron-withdrawing group(s), ii)3,4-dihydropyran 2r,a nd iii)1,1-disubstituted aliphatic alkenes 2s-u.T hese reactions gave 4ja,jb,jd,jf, 4kd-nd,pd, 4qa, 4sa-ua in up to 97 % isolated yield (acyla zides as limiting reagent) and 4od,rd in 87-90 %i solated yields (substrates as limiting reagent) (Figure 4);w ith 4od,qa,rd (from cis alkenes) all adopting cis configuration and 4nd (from trans alkene) adopting trans configuration.…”

“…TheR u(Por)/N 3 COR method for catalytic acylnitrene transfer is applicable to functionalization of natural products and carbohydrate derivatives (as limiting reagents), including pinenes 11 a,b and chromene/carbohydrate derivatives 11 c-f (Scheme 1), which are not among the substrates employed in previous reports on metal-catalyzed acylnitrene transfer reactions. [5][6][7][8][9][10][11][12][13][14][15][16] [34] Application to Nucleophilic Ring-Opening of in Situ Generated N-Acyl Aziridines Ring-opening reactions of N-acyl aziridines by nucleophiles give 1,2-bis-functionalizeda mino derivatives, [35] which…”

“…[5] In 2000, we reported CÀHa mination of ethylbenzene by,e .g., Ru III -(Me 3 tacn)/H 2 NCOPh. [6,7] Recently,there is asurge of interest in C À Ha mination with acyl azides N 3 COR (1), dioxazolones, [8] H 2 NCOCF 3 ,orN-substituted amides H(R'O)NCOR, as reported by Chang and others [9,10,[12][13][14][15] employing directing group (DG) strategy (for intermolecular reactions) and by Warren and co-workers [11] using Cu I (diketiminate)/N 3 COR for hydrocarbons without DGs.T hese reactions proceed via proposed M(NCOR) intermediates (Figure 1aA, M = Fe, [5,9] Co, [10] Cu, [7a, 11] Ru, [6,12] Rh, [13,14] Ir, [8, 13c, 15] Au [7b] ). M(NCOR) (M = Cu, [16c,g] Ru, [16a,b,d,h] Ir [16e,f] )i ntermediates were also proposed in the corresponding catalytic reactions to give sulfimides,o xazoles,o xazolines,l actams,a nd amidines.…”

Recent Progress in the C−N Bond Formation via High‐Valent Group 9 Cp*M(III)‐Catalyzed Directed sp2 C−H Activation

“…Adding on, in producing derivatives of 7‐azaindoles 34 , Dong and co‐workers [17b] reported the dual reactivity of acyl azides 4 as an amino or carbon source depending upon the catalytic system studied. While in the presence of Ir(III)‐catalyst amidation took place employing the acyl azides, Rh(III)‐catalytic system promoted the anilide formation by using the in situ generated isocyanate from the azides (Scheme 39).…”