70156-86-4

Upstream product

• 495-18-1 Benzohydroxamic acid 
• 1165952-91-9 cyclohexa-1,3-diene 
• 20594-92-7 3,5-diphenyl-1,2,4-oxadiazole-4-oxide 
• 93-58-3 benzoic acid methyl ester 
• 188118-33-4 3-anisyl-5-phenyl-1,2,4-oxadiazole-4-oxide 
• 186665-02-1 5-phenyl-3-p-tolyl-1,2,4-oxadiasole-4-oxide 
• 698-16-8 benzohydroximoyl chloride 

Downstream Products

• 146309-11-7 cis-4-(benzoylamino)cyclohexanol 

Relevant academic research and scientific papers

Photocatalyzed Generation of Nitrosocarbonyl Intermediates Under Solar Light Irradiation

Tetrabutylammonium decatungstate (TBADT) has emerged as a valuable photocatalyst for sunlight-induced organic reactions. In this communication we wish to present its use for the photocatalytic oxidation of hydroxamic acids to generate fleeting nitrosocarb

Oxidative cycloaddition of hydroxamic acids with dienes or guaiacols mediated by iodine(III) reagents

[Bis(trifluoroacetoxy)iodo]benzene (BTI) and (diacetoxyiodo)benzene (DIB) efficiently promote the formation of acylnitroso species from hydroxamic acids in the presence of various dienes to give the corresponding hetero-Diels-Alder (HDA) adducts in moderate to high yields. The present method could be applied to the HDA reactions of acylnitroso species with o-benzoquinones generated by the oxidative dearomatization of guaiacols.

Hetero Diels–Alder Reaction and Ene Reaction of Acylnitroso Species in situ Generated by Hypoiodite Catalysis

As a first non-metal-catalyzed oxidation for the in situ generation of acylnitroso species, we describe the hypoiodite catalysis using tetra-n-butylammonium iodide as precatalyst with tert-butyl hydroperoxide or hydrogen peroxide as a terminal oxidant. Th

A new synthetic route to acylnitroso intermediates and their applications in HDA and ene reactions

Background: Acylnitroso intermediates are considered as highly reactive and useful transient that have been used to synthesize a broad class of biological active compounds and synthetic drugs. Although there are some reported methods for the generation of these intermediates, but still challenge for mild and environmental benign protocol. Herein, we report the facile in situ synthesis of acylnitroso intermediates and their efficient hetero Diels-Alder (HDA) and ene reactions. Methods: Acylnitroso intermediates were readily obtained by hydrogen peroxide oxidation of hydroxamic acids catalyzed by Cu(I)-, Ir(I)- or Ru(II)-complexes and easily reacted with symmetric and asymmetric conjugated dienes beside their reaction with different alkenes which converted to biological active products. Results: The resulted acylnitroso intermediates were efficiently afforded the hetero Diels-Alder cycloadducts in the presence of cyclopentadiene, cyclohexadiene or α-terpinene in high yields along with good regioselectivity for the later. In case of N-dienyl lactams, the cycloadducts were formed in the yield up to 89% with complete regioselectivity. In the presence of optically active N-dienyl pyroglutamates, diastereoisomers were formed in high yields with up to 72 de. In addition, the transient acylnitroso species were trapped with alkene to form the ene product in yield up to 95 %. As an interesting transformation, the halocyclization of the ene products gave substituted oxazolidone in 77% yield which considered as one of the effective antimicrobial and antibiotic compounds. Conclusion: In a brief, we introduce a mild and effective route to deliver acylnitroso intermediates in situ by using environmentally benign, cost effective, and non-toxic hydrogen peroxide oxidant catalyzed by Cu(I)-, Ir(I)- or Ru(II)-complexes. Good to excellent yields, regio- and diastereoselectivity were obtained by trapping these intermediates in symmetric and asymmetric HDA and ene reactions. Interestingly, the ene products easily transformed to potent drugs.

An Experimental and Computational Approach to Understanding the Reactions of Acyl Nitroso Compounds in [4 + 2] Cycloadditions

Catalytic aerobic oxidation of phenyl hydroxycarbamate 1 and 1-hydroxy-3-phenylurea 2 using CuCl2 and 2-ethyl-2-oxazoline in methanol gave acyl nitroso species in situ, which were trapped in nitroso-Diels-Alder (NDA) reactions with various dienes to afford the corresponding cycloadducts in high yields (90-98%). Competing ene products were also present for dienes containing both alkene π-bonds and allylic σ-bonds, and the ene yields are higher with 1 than with 2. The use of the chiral hydroxamic acid, (R)-1-hydroxy-3-(1-phenylethylurea) 3 (same conditions) gave NDA cycloadducts in high yields (97-99%) with no ene product from 2,3-dimethyl-1,3-butadiene. NDA cycloadducts were not obtained from other hydroxamic acid analogues [RCONHOH (R = PhCH2 4; Ph(CH2)2 5; Ph(CH2)3 6; Ph(CH2)4 7; Ph 8; 2-pyridyl 9; 3-pyridyl 10] with various dienes using copper-oxidation but rather were obtained using sodium periodate, resulting in variable NDA yields (13-51%) from hydroxamic acids 1-10 with cyclohexa-1,3-diene and 2,3-dimethyl-1,3-butadiene (several cycloadducts characterized by X-ray crystallography). The NDA and nitroso-ene reaction pathways of nitroso intermediates with dienes were mapped by DFT computations (B3LYP/6-31G), which showed that the acyl nitroso species are super-reactive and that activation energies in the NDA processes are lower than the isomerization barriers between some cis- and trans-butadienes.

Copper-catalyzed aerobic oxidation of N-substituted hydroxylamines: Efficient and practical access to nitroso compounds

A general and efficient aerobic oxidation of N-substituted hydroxylamines is described. The mild reaction conditions employed provide a catalytic and sustainable alternative to stoichiometric oxidation methods to gain access to a range of nitroso compound

Direct observation of an Acyl nitroso species in solution by time-resolved IR spectrocopy

Benzoyl nitroside (5) was generated in solution by laser photolysis of 3,5-diphenyl-1,2,4-oxadiazole-4-oxide (4) and studied by time-resolved infrared spectroscopy. The second-order rate constantsfor reaction of 5 with diethylamine and 1,3-cyclohexadiene were determined to be (1.3 ± 0.5) × 105 M-1 s-1 and (6.0 ± 0.5) × 103 M-1 s-1, respectively. The formation of nitroxyl (HNO), a product of the reaction of 5 with diethylamine, was also observed. Copyright

Generation of acyl nitroso compounds by the oxidation of N-acyl hydroxylamines with the Dess-Martin periodinane

The oxidation of hydroxamic acids, N-hydroxyureas and N- hydroxycarbamates with the Dess-Martin periodinane generates the corresponding acyl nitroso compounds that react with conjugated dienes to produce the corresponding cycloadducts.

A photochemical generation of nitrosocarbonyl intermediates

Nitrosocarbonyl intermediates are photochemically generated from 1,2,4- oxadiazole-4-oxides and efficiently trapped with enes and dienes.

The mild oxidation of nitrile oxides affords a convenient entry to nitrosocarbonyl intermediates, versatile tools in organic syntheses

Nitrile oxides are oxidized by tertiary amine N-oxides in different solvents at room temperature to afford in the presence of dienes nitrosocarbonyl adducts in fair yields. The mild conditions used in oxidizing a variety of nitrile oxides promise a wide application of this method in synthetic processes.