Detail of "16466-61-8"

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Domino Cu-catalyzed C-N coupling/hydroamidation: a highly efficient synthesis of nitrogen heterocycles

All Rights Reserved. Several substances are used for example 16466-61-8 and 919123-86-7 which are their cas registry numbers. Domino Cu-catalyzed C-N coupling/hydroamidation: a highly efficient synthesis of nitrogen heterocycles. Martin, Ruben; Rivero, Marta Rodriguez; Buchwald, Stephen L. ( Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA). Angewandte Chemie, International Edition, 45(42), 7079-7082 (English) 2006 Wiley-VCH Verlag GmbH & Co. KGaA. CODEN: ACIEF5. ISSN: 1433-7851. DOCUMENT TYPE: Journal CA Section: 28 (Heterocyclic Compounds (More Than One Hetero Atom)) Section cross-reference(s): 27 Boc-protected pyrroles and fused pyrroles and pyrazoles and fused pyrazoles with a variety of substituents are prepd. by copper-catalyzed coupling and hydroamidation reactions of iodo- or bromoalkenynes and iodo- or bromoaryl alkynes with either tert-Bu carbamate or di-tert-Bu hydrazinedicarboxylate. Iodoenynes RCI:CR1CYCR2 [R = EtCH2, Bu, Ph, 1-cyclohex-1-enyl, TIPSOCH2, MeO2C, TBS; R1 = H, EtCH2, 4-MeC6H4; RR1 = (CH2)3; R2 = H, EtCH2, Bu, BuCH2, 1-cyclohex-1-enyl, Ph, Cl(CH2)3, Me(CH2)7, 4-MeC6H4; TIPS = triisopropylsilyl; TBS = tert-butyldimethylsilyl] undergo coupling and hydroamidation reactions with BocNH2 in the presence of copper (I) iodide and N,N'-dimethylethylendiamine with cesium carbonate as a base in THF at 80° to give 1-Boc-pyrroles I [R = EtCH2, Bu, Ph, 1-cyclohex-1-enyl, TIPSOCH2, MeO2C, TBS; R1 = H, EtCH2, 4-MeC6H4; RR1 = (CH2)3; R2 = H, EtCH2, Bu, BuCH2, 1-cyclohex-1-enyl, Ph, Cl(CH2)3, Me(CH2)7, 4-MeC6H4; Boc = tert-butoxycarbonyl] in 52-95% yields; bromoenynes can be used when the reaction is performed in toluene (with potassium carbonate as the base) at 110°. Bromothienyl alkynes and an iodopyridinyl alkyne undergo copper-catalyzed cyclocondensation with tert-Bu carbamate under similar conditions to give thienopyrroles and a pyrrolopyridine, resp. Iodoenynes RCI:CR1CYCR2 [R = H, EtCH2, Bu, Ph, PhCH2, TIPSOCH2; R1 = H, Et; RR1 = (CH2)3; R2 = H, EtCH2, BuCH2, Me(CH2)7, Ph, Cl(CH2)3, PhCH2O(CH2)2, EtO2C] undergo coupling and hydroamidation reactions with BocNH2 in the presence of copper (I) iodide and N,N'-dimethylethylendiamine with cesium carbonate as a base in THF at 80° followed by deprotection with F3CCO2H in CH2Cl2 to give pyrazoles II [R = H, EtCH2, Bu, Ph, PhCH2, TIPSOCH2; R1 = H, Et; RR1 = (CH2)3; R2 = H, EtCH2, BuCH2, Me(CH2)7, Ph, Cl(CH2)3, PhCH2O(CH2)2, EtO2C] in 66-93% yields. Ligands for the cyclocondensation are tested; only N,N'-dimethylethylenediamine and N,N'-dimethyl-trans-1,2-cyclohexanediamine are effective. The coupling and hydroamidation reactions require the presence of both the copper catalyst and ligand and added base. The prepns. of most of the iodoenyne and bromoenyne starting materials (as well as those of the bromothienyl alkynes and the iodopyridinyl alkyne) are described. Amine and hydrazine coupling products with an iodoenyne and a alkylidenedihydropyrazoledicarboxylate intermediate in the prepn. of a pyrazole are isolated, supporting a coupling-hydroamidation pathway (rather than a hydroamidation-coupling pathway) for the reaction. .