88048-43-5Relevant articles and documents
Diamine Synthesis via the Nitrogen-Directed Azidation of σ- And π-C-C Bonds
Nguyen, Tin V. T.,Wang, Ming-Ming,Waser, Jerome
supporting information, p. 11969 - 11975 (2021/08/24)
Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. We report herein a new strategy giving access to 1,2, 1,3, and 1,4 amido azides as orthogonally protected diamines based on the nitrogen-directed diazidation of alkenes, cyclopropanes, and cyclobutanes. Commercially available copper thiophene-2-carboxylate (CuTc, 2 mol %) as catalyst promoted the diazidation of both πand σ C-C bonds within 10 min in the presence of readily available oxidants and trimethylsilyl azide. Selective substitution of the formed α-amino azide by carbon nucleophiles (electron-rich aromatic, malonate, organosilicon, organoboron, organozinc, and organomagnesium compounds) was then achieved in a one-pot fashion, leading to the formation of 1,2-, 1,3-, and 1,4-diamines with the amino groups protected orthogonally as an amide/carbamate and an azide.
Synthesis of thiochromans via [3+3] annulation of aminocyclopropanes with thiophenols
Wang, Ming-Ming,Jeon, Seongmin,Waser, Jer?me
supporting information, p. 9123 - 9127 (2020/11/30)
We report the one-pot synthesis of 4-amino thiochromans using simple aminocyclopropanes and thiophenols through a formal [3+3] annulation reaction. This reaction proceeds under mild conditions with good functional group tolerance. The thiochroman core was
σ-Bond Hydroboration of Cyclopropanes
Arifin,Itami, Kenichiro,Kato, Hiroki,Kobayashi, Chisa,Kondo, Hiroki,Matsushita, Kaoru,Miyamura, Shin,Yamaguchi, Junichiro,Yokogawa, Daisuke
supporting information, p. 11306 - 11313 (2020/07/13)
Hydroboration of alkenes is a classical reaction in organic synthesis in which alkenes react with boranes to give alkylboranes with subsequent oxidation resulting in alcohols. The double bond (π-bond) of alkenes can be readily reacted with boranes owing to its high reactivity. However, the single bond (σ-bond) of alkanes has never been reacted. To pursue the development of σ-bond cleavage, we selected cyclopropanes as model substrates since they present a relatively weak σ-bond. Herein, we describe an iridium-catalyzed hydroboration of cyclopropanes, resulting in β-methyl alkylboronates. These unusually branched boronates can be derivatized by oxidation or cross-coupling chemistry, accessing "designer"products that are desired by practitioners of natural product synthesis and medicinal chemistry. Furthermore, mechanistic investigations and theoretical studies revealed the enabling role of the catalyst.
Carbamate Synthesis Using a Shelf-Stable and Renewable C1 Reactant
Dobi, Zoltán,Reddy, B. Narendraprasad,Renders, Evelien,Van Raemdonck, Laurent,Mensch, Carl,De Smet, Gilles,Chen, Chen,Bheeter, Charles,Sergeyev, Sergey,Herrebout, Wouter A.,Maes, Bert U. W.
, p. 3103 - 3114 (2019/06/24)
4-Propylcatechol carbonate is a shelf-stable, renewable C1 reactant. It is easily prepared from renewable 4-propylcatechol (derived from wood) and dimethyl carbonate (derived from CO2) using a reactive distillation system. In this work, the 4-propylcatechol carbonate is used for the two-step synthesis of carbamates under mild reaction conditions. In the first step, 4-propylcatechol carbonate is treated with an alcohol at 50–80 °C in the presence of a Lewis acid catalyst, such as Zn(OAc)2?2 H2O. With liquid alcohols, no solvent is used and with solid alcohols 2-methyltetrahydrofuran is used as solvent. In the second step, the alkyl 2-hydroxy-propylphenyl carbonate intermediates obtained react with amines at room temperature in 2-methyltetrahydrofuran, forming the target carbamates and the byproduct 4-propylcatechol, which can be recycled into a carbonate reactant.
1,3-Difunctionalization of Aminocyclopropanes via Dielectrophilic Intermediates
Wang, Ming-Ming,Waser, Jér?me
supporting information, p. 13880 - 13884 (2019/08/30)
We report an oxidative ring-opening strategy to transform acyl, sulfonyl or carbamate protected aminocyclopropanes into 1,3-dielectrophilic carbon intermediates bearing a halide atom (Br, I) and a N,O-acetal. Replacing the alkoxy group of the N,O-acetal can be achieved under acidic conditions through an elimination–addition pathway, while substitution of the halides by nucleophiles can be done under basic conditions through a SN2 pathway, generating a wide range of 1,3-difunctionalized propylamines. A proof of concept for asymmetric induction was realized using a chiral phosphoric acid (CPA) as catalyst, highlighting the potential of the method in enantioselective synthesis of important building blocks.
Reversible C-C bond activation enables stereocontrol in Rh-catalyzed carbonylative cycloadditions of aminocyclopropanes
Shaw, Megan H.,McCreanor, Niall G.,Whittingham, William G.,Bower, John F.
supporting information, p. 463 - 468 (2015/01/30)
Upon exposure to neutral or cationic Rh(I)-catalyst systems, amino-substituted cyclopropanes undergo carbonylative cycloaddition with tethered alkenes to provide stereochemically complex N-heterocyclic scaffolds. These processes rely upon the generation and trapping of rhodacyclopentanone intermediates, which arise by regioselective, Cbz-directed insertion of Rh and CO into one of the two proximal aminocyclopropane C-C bonds. For cyclizations using cationic Rh(I)-systems, synthetic and mechanistic studies indicate that rhodacyclopentanone formation is reversible and that the alkene insertion step determines product diastereoselectivity. This regime facilitates high levels of stereocontrol with respect to substituents on the alkene tether. The option of generating rhodacyclopentanones dynamically provides a new facet to a growing area of catalysis and may find use as a (stereo)control strategy in other processes.
Synthesis and characterization of 5H-1,3-dioxolo[4,5-f]indoleethylamines
Grotjahn
, p. 1031 - 1036 (2007/10/02)
Twelve new N,N-dialkylated-5,6-methylenedioxytryptamines and N-cyclopropyl-5,6-methylenedioxytryptamine were prepared as hybrids of known psychoactive phenylethylamines and tryptamines. Novel, more convenient synthesis of N-methyl- and N-benzylcyclopropyl
