46707-86-2

Upstream product

• 6289-87-8 N-(2-(hydroxymethyl)phenyl)benzamide 
• 95207-34-4 N-benzoyl 1H-3,4-dihydro-2,1-benzoxazepine 
• 108-93-0 cyclohexanol 
• 82085-86-7 2-phenyl-1,4-dihydro-2H-benz[d][1,3]oxazine 
• 100-52-7 benzaldehyde 
• 5344-90-1 2-Aminobenzyl alcohol 
• 584-70-3 N-benzoyl-2-methylaniline 
• 98-88-4 benzoyl chloride 
• 95-53-4 o-toluidine 
• 115975-86-5 3-(2-hydroxymethylanilino)-3-phenylprop-2-enenitrile 

Downstream Products

• 75541-90-1 N-benzoyl-2-methoxymethylaniline 
• 31590-14-4 2-aminobenzyl benzoate 
• 1022-46-4 2-phenyl-4H-3,1-benzoxazin-4-one 
• 33768-43-3 N-(2-formylphenyl)benzamide 
• 25855-20-3 2-phenylquinazoline 

Relevant academic research and scientific papers

N-Heterocyclic Carbene Catalysis Exploiting Oxidative Imine Umpolung for the Generation of Imidoyl Azoliums

Although NHC-catalyzed umpolung of imines are known, the related reactions under oxidative conditions are limited. Described herein is the two-step process involving the initial formation of aldimines from the corresponding aldehydes and 2-amino benzyl alcohols followed by NHC-catalyzed cyclization proceeding via the imidoyl azoliums under oxidative conditions. The reaction allowed the synthesis of trifluoromethylated 3,1-benzoxazines in good yields and broad scope. The role of NHC in the intramolecular cyclization and preliminary mechanistic experiments are also provided.

ABNO-Catalyzed Aerobic Oxidative Synthesis of 2-Substituted 4H-3,1-Benzoxazines and Quinazolines

A new transition-metal-free 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO) catalyzed aerobic oxidative synthesis of 2-substituted 4H-3,1-benzoxazines and quinazolines has been developed through cascade reaction of aldehydes with 2-aminobenzyl alcohols and 2-amino

Catalytic oxidation synthesis method of 4H-3,1-benzoxazine compound

The invention discloses a catalytic oxidation synthesis method of a 4H-3,1-benzoxazine compound. The method comprises the following steps: using a 2-aminobenzyl alcohol compound and aldehyde as reaction substrates in a molar ratio of 100: (100 to 120), us

Synthesis of 2-substituted quinazolines via iridium catalysis

An iridium-catalyzed hydrogen transfer reaction was successfully applied in the synthesis of 2-substituted quinazolines in moderate yields starting from aldehydes or alcohols with 2-aminobenzylamines.

CuCl/DABCO/4-HO-TEMPO-catalyzed aerobic oxidative synthesis of 2-substituted quinazolines and 4 H -3,1-benzoxazines

The Cu/N-ligand/TEMPO catalytic system was first applied to the aerobic oxidative synthesis of heterocycles. As demonstrated, 2-substituted quinazolines and 4H-3,1-benzoxazines were synthesized efficiently from the one-pot reaction of aldehydes with 2-aminobenzylamines and 2-aminobenzyl alcohols, respectively, by employing CuCl/DABCO/4-HO-TEMPO as the catalysts and oxygen as the terminal oxidant.

Copper-catalyzed selective benzylic C-O cyclization of N-o-tolylbenzamides: Synthesis of 4 H-3,1-benzoxazines

A novel Selectfluor-mediated copper-catalyzed highly selective benzylic C-O cyclization for the synthesis 4H-3,1-benzoxazines is reported. The predominant selectivity for a benzylic C(sp3)-H over an aromatic C(sp 2)-H bond in N-o-tolylbenzamides is achieved.

Synthesis of 3h-quinazolin-4-ones and 4h-3,1-benzoxazin-4-ones via benzylic oxidation and oxidative dehydrogenation using potassium iodide-tert-butyl hydroperoxide

A simple and elegant method for benzylic activation was demonstrated employing the potassium iodide/tert-butyl hydrogen peroxide catalytic system. This methodology was further extended for the synthesis of biologically important heterocycles namely, 3H-quinazolin-4-ones and 4H-3,1-benzoxazin-4-ones including mecloqualone and etaqualone which are important quinazolinone-based drugs used for the treatment of insomnia in good yields.

Highly efficient one-pot synthesis of 2-substituted quinazolines and 4H-benzo[d][1,3]oxazines via cross dehydrogenative coupling using sodium hypochlorite

This communication describes a catalyst-free synthesis of 2-substituted quinazolines and 4H-benzo[d][1,3]oxazines using commericially available sodium hypochlorite as oxidant. Operational simplicity, mild reaction conditions and the ability to construct structurally diverse 2-quinazolines and 2-substituted 4H-benzo[d][1,3]oxazines by this method render it to be a practical alternative for the synthesis of these heterocycles.

Kinetics and mechanism of the addition of water and ring-opening of 2-methyl- and 2-aryl-4H-3,1-benzoxazines to 2-aminobenzyl esters in the acidic pH range; change in rate-limiting step with buffer concentration and evidence for a tetrahedral carbonyl addition intermediate

The observed rate coefficients for the reaction of 2-methyl-, 2-phenyl- and 2-(4-nitrophenyl)-4H-3,1-benzoxazines to give the corresponding 2-aminobenzyl esters increase as the pH is lowered and reach a constant plateau value at pH 2-4 depending on the substituent. The plateau region corresponds to complete conversion of the benzoxazine to the protonated benzoxazine (SH+) which is the reactive species. Values of pKSH+ calculated by fitting the appropriate rate expression to the rate-pH profile and the pKSH+ values measured spectrophotometrically before significant reaction to the ester has taken place are in good agreement. For each benzoxazine the observed rate coefficients show a rectilinear dependence on buffer concentration. A mechanism is proposed involving addition of water to the protonated benzoxazine to give a cyclic tetrahedral carbonyl addition intermediate. At low buffer concentrations, buffer catalysed collapse of the intermediate to product is rate-limiting and the reaction is first order in buffer. At high buffer concentrations, collapse of the intermediate to product is rapid and addition of water to the protonated benzoxazine to give the intermediate is rate-limiting.

Rearrangement of N-acyl-3,4-dihydro-1H-2,1-benzoxazines to 2-substituted-4H-3,1-benzoxazines through a retro-Diels-Alder extrusion of formaldehyde

N-Acyl-3,4-dihydro-1H-2,1-benzoxazines (3) undergo a thermal decomposition involving loss of formaldehyde in a retro-Diels-Alder reaction. The resultant N-acylazaxylylenes? (4) undergo a 6π electrocyclisation to give 2-substituted-4H-3,1-benzoxazines (5) rather than a 4π electrocyclisation to give the N-acyl-1,2-dihydrobenzazetes (6). Compounds 5 have been fully characterised spectroscopically and their data is inconsistent with that reported previously by other workers for what are purported to be the same compounds. 2-Methyl-4H-3,1-benzoxazine (5b) and other 2-alkyl-substituted compounds undergo facile hydrolysis to o-aminobenzyl esters (9) which rearrange to the thermodynamically more stable o-hydroxymethylanilides (10). 2-Phenyl-4H-3,1-benzoxazine (5a) is relatively stable to hydrolysis but undergoes a novel photochemical ring opening (> 254 nm) to give the N-benzoylazaxylylene (12) which can be trapped with alcohols giving o′-alkoxymethylbenzanilides (11). In cyclohexanol at 160°C, the intermediate in the thermal rearrangement of 3a to 5a, N-benzoylazaxylylene (12), was trapped as o′-cyclohexyloxymethylbenzanilide (11b). The rearrangements in mesitylene are unimolecular with activation energies of 35, 37 and 42 kcal mol-1 ? for 3a; 3c and 3d, respectively. The extrusion and electrocyclisation reaction pathways for N-acetyl-3,4-dihydro-2,1- benzoxazine (3b) have been modelled using AM1 molecular orbital theory which predicts both a non-synchronous transition state for the retro-Diels-Alder reaction and the preferred mode of ring closure to be the 6π rather than the 4π electrocyclisation.