Straightforward and Expeditious One-Pot Tandem Synthesis of 3,5-Diaryl-1,2,4-Selenadiazoles from Aryl Nitriles

A Cu-catalyzed carbonylative borylation of unactivated alkyl halides has been developed, enabling efficient synthesis of aliphatic potassium acyltrifluoroborates (KATs) in high yields by treating the in-situ formed tetracoordinated acylboron intermediates with aqueous KHF2. A variety of functional groups are tolerated under the mild reaction conditions, and primary, secondary and tertiary alkyl halides are all applicable. In addition, this method also provides facile access to N-methyliminodiacetyl (MIDA) acylboronates as well as α-methylated potassium acyltrifluoroborates in a one-pot manner. Mechanistic studies indicate a radical atom transfer carbonylation (ATC) mechanism to form acyl halide intermediates that are subsequently borylated by (NHC)CuBpin.

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2-Phenyl-2,3-dihydrobenzo[d]thiazole: A Mild, Efficient, and Highly Active in situ Generated Chemoselective Reducing Agent for the One-Pot Synthesis of 5-Monoalkylbarbiturates in Water

Synlett ◽

10.1055/s-0036-1591725 ◽

2017 ◽

Vol 29 (04) ◽

pp. 477-482 ◽

Cited By ~ 1

Author(s):

Dibakar Deka ◽

Subarna Kalita

Keyword(s):

Reducing Agent ◽

High Yield ◽

Purification Process ◽

Reaction Conditions ◽

One Pot ◽

One Pot Synthesis ◽

Highly Active ◽

The One ◽

Operational Simplicity

A metal- and catalyst-free reductive alkylation protocol for the one-pot synthesis of 5-monoalkylbarbiturates from barbituric acids and aldehydes using the in situ generated chemoselective reducing agent 2-phenyl-2,3-dihydrobenzo[d]thiazole from 2-aminothiophenol and benzaldehyde is described. The notable advantages of the protocol are operational simplicity, mild reaction conditions, high yield, short reaction time, and simple workup and purification process which make it highly attractive.

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One-Step Synthesis of Acylboron Compounds via Cu-Catalyzed Carbonylative Borylation of Alkyl Halides

10.26434/chemrxiv.12818180.v1 ◽

2020 ◽

Author(s):

Cheng Li-Jie ◽

Zhao Siling ◽

Neal Mankad

Keyword(s):

Alkyl Halides ◽

Efficient Synthesis ◽

Mechanistic Studies ◽

Acyl Halide ◽

Reaction Conditions ◽

One Pot ◽

One Step ◽

High Yields ◽

Tertiary Alkyl

A Cu-catalyzed carbonylative borylation of unactivated alkyl halides has been developed, enabling efficient synthesis of aliphatic potassium acyltrifluoroborates (KATs) in high yields by treating the in-situ formed tetracoordinated acylboron intermediates with aqueous KHF2. A variety of functional groups are tolerated under the mild reaction conditions, and primary, secondary and tertiary alkyl halides are all applicable. In addition, this method also provides facile access to N-methyliminodiacetyl (MIDA) acylboronates as well as α-methylated potassium acyltrifluoroborates in a one-pot manner. Mechanistic studies indicate a radical atom transfer carbonylation (ATC) mechanism to form acyl halide intermediates that are subsequently borylated by (NHC)CuBpin.

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One-Pot Synthesis of Novel Multisubstituted 1-Alkoxyindoles

Molecules ◽

10.3390/molecules26051466 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1466

Author(s):

Ye Eun Kim ◽

Hyunsung Cho ◽

Yoo Jin Lim ◽

Chorong Kim ◽

Sang Hyup Lee

Keyword(s):

Alkyl Halide ◽

The Novel ◽

Reaction Conditions ◽

One Pot ◽

One Pot Synthesis ◽

Consecutive Reactions ◽

Intramolecular Condensation ◽

Synthetic Sequence ◽

Novel Target

Studies on a one-pot synthesis of novel multisubstituted 1-alkoxyindoles 1 and their mechanistic investigations are presented. The synthesis of 1 was successfully achieved through consecutive four step reactions from substrates 2. The substrates 2, prepared through a two-step synthetic sequence, underwent three consecutive reactions of nitro reduction, intramolecular condensation, and nucleophilic 1,5-addition to provide the intermediates, 1-hydroxyindoles 8, which then were alkylated in situ with alkyl halide to afford the novel target products 1. We optimized the reaction conditions for 1 focusing on the alkylation step, along with the consideration of formation of intermediates 8. The optimized condition was SnCl2·2H2O (3.3 eq) and alcohols (R1OH, 2.0 eq) for 1–2 h at 40 °C and then, base (10 eq) and alkyl halides (R2Y, 2.0 eq) for 1–4 h at 25–50 °C. Notably, all four step reactions were performed in one-pot to give 1 in good to modest yields. Furthermore, the mechanistic aspects were also discussed regarding the reaction pathways and the formation of side products. The significance lies in development of efficient one-pot reactions and in generation of new 1-alkoxyindoles.

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A Simple and Efficient Synthesis of Highly Substituted Indeno[1,2-b]pyrrole and Acenaphtho[1,2-b]pyrrole Derivatives by Tandem Three-Component Reactions

Molecules ◽

10.3390/molecules23113031 ◽

2018 ◽

Vol 23 (11) ◽

pp. 3031 ◽

Cited By ~ 2

Author(s):

Xiaodong Tang ◽

Songlei Zhu ◽

Ying Ma ◽

Ren Wen ◽

Lanqi Cen ◽

...

Keyword(s):

Environmentally Benign ◽

Efficient Synthesis ◽

Reaction Conditions ◽

Dicarbonyl Compounds ◽

Pyrrole Derivatives ◽

Three Component Reaction ◽

High Yields ◽

Operational Simplicity

A green, convenient and tandem procedure for the efficient synthesis of highly substituted indeno[1,2-b]pyrrole and acenaphtho[1,2-b]pyrrole derivatives by domino three-component reaction of tryptamine/benzylamine, 1,3-dicarbonyl compounds and ninhydrin/ acenaphthenequinone is described. The significant features of this procedure were characterized by mild reaction conditions, high yields, operational simplicity and it being environmentally benign.

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Ligand-Free (Z)-Selective Transfer Semihydrogenation of Alkynes Catalyzed by in situ Generated Oxidizable Copper Nanoparticles

10.26434/chemrxiv.13635272 ◽

2021 ◽

Author(s):

Rafał Kusy ◽

Karol Grela

Keyword(s):

Suzuki Reaction ◽

Ammonia Borane ◽

Water Soluble ◽

Selective Transfer ◽

One Pot ◽

Ammonia Complex ◽

Ligand Free ◽

Simple Phase ◽

Operational Simplicity

Herein, we present (Z)-selective transfer semihydrogenation of alkynes based on in situ generated CuNPs in the presence of hydrogen donors, such as ammonia-borane and a protic solvent. This environmentally-friendly method is characterized by operational simplicity combined with high stereo- and chemoselectivity and functional group compatibility. Auto-oxidation of CuNPs after the semihydrogenation reaction is completed results in the formation of water-soluble ammonia complex, so that the catalyst may be reused several times by simple phase-separation with no need of any special regeneration process. Formed NH4B(OR)4 can be easily transformed back to ammonia-borane or to boric acid. In addition, one-pot tandem sequence involving Suzuki reaction followed by semihydrogenation was presented.

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Appel-reagent-mediated transformation of glycosyl hemiacetal derivatives into thioglycosides and glycosyl thiols

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.9.112 ◽

2013 ◽

Vol 9 ◽

pp. 974-982 ◽

Cited By ~ 8

Author(s):

Tamashree Ghosh ◽

Abhishek Santra ◽

Anup Kumar Misra

Keyword(s):

Reaction Sequence ◽

Reaction Conditions ◽

One Pot ◽

Carbon Tetrabromide

A series of glycosyl hemiacetal derivatives have been transformed into thioglycosides and glycosyl thiols in a one-pot two-step reaction sequence mediated by Appel reagent (carbon tetrabromide and triphenylphosphine). 1,2-trans-Thioglycosides and β-glycosyl thiol derivatives were stereoselectively formed by the reaction of the in situ generated glycosyl bromides with thiols and sodium carbonotrithioate. The reaction conditions are reasonably simple and yields were very good.

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Visible-Light Photoredox-Catalyzed Cascade Reaction for the Synthesis of Pyrrolo[2,1-a]isoquinoline-Substituted Phosphonates

Synthesis ◽

10.1055/s-0037-1610907 ◽

2018 ◽

Vol 51 (02) ◽

pp. 522-529 ◽

Cited By ~ 3

Author(s):

Deqing Shi ◽

Lingna Wang ◽

Tiancong Ma ◽

Mingming Qiao ◽

Qiangxian Wu ◽

...

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Room Temperature ◽

Cascade Reaction ◽

Efficient Synthesis ◽

Reaction Conditions ◽

One Pot ◽

Oxidative Aromatization ◽

Activated Olefins ◽

Catalyzed Oxidation

A visible-light photoredox-catalyzed oxidation/[3+2] cycloaddition/oxidative aromatization cascade reaction of [(3,4-dihydroisoquinolin-2(1H)-yl)methyl]phosphonates and activated olefins or alkynes for the efficient synthesis of potentially biological active pyrrolo[2,1-a]isoquinoline-substituted phosphonates was developed. This transformation features mild reaction conditions (i.e., visible light irradiation, room temperature), molecular oxygen (O2) as a green oxidant, simple ‘one-pot’ operation.

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A novel Pd-catalysed sequential carbonylation/cyclization approach toward bis- N -heterocycles: rationalization by electronic structure calculations

Royal Society Open Science ◽

10.1098/rsos.181140 ◽

2018 ◽

Vol 5 (9) ◽

pp. 181140 ◽

Cited By ~ 4

Author(s):

Liliana Damas ◽

Rui M. B. Carrilho ◽

Sandra C. C. Nunes ◽

Alberto A. C. C. Pais ◽

László Kollár ◽

...

Keyword(s):

Electronic Structure ◽

Electronic Structure Calculations ◽

Reaction Conditions ◽

One Pot ◽

New Family ◽

Synthetic Strategy ◽

Heterocyclic Derivatives ◽

Amine Groups ◽

Structure Calculations

An unprecedented palladium-catalysed sequential aminocarbonylation/cyclization synthetic strategy, using carbon monoxide and structurally different aliphatic diamines as N -nucleophiles, gives access, in one pot, to a new family of indole-based N -heterocyclic derivatives (hydropyrazinones, benzodiazepinones and hydroquinoxalines). Optimization of the reaction conditions towards double carbonylation ( P CO = 30 bar, T = 80°C, iodoindole/diamine ratio = 1 : 1.5, toluene as solvent) allowed the target cyclic products, which are formed in situ via intramolecular cyclization of the ketocarboxamide intermediates, to be obtained through a nucleophilic addition/elimination reaction with the pendant terminal amine groups. The structure of the diamine nucleophile was revealed to affect the reaction's selectivity, with the best yields for the cyclic products being obtained in the presence of (1 S , 2S )-(+)-cyclohexane-1,2-diamine ( a ) as the nucleophile, using either 5- or 7-iodoindole as the substrate. The reaction's selectivity was rationalized based on electronic structure calculations, which explain the effect of the diamine structure on the predominant formation of the cyclic products.

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