N benzylidene

Irradiation of 1,2,3-triphenylaziridine (98) in various alcohols has been reported to give benzaldehyde acetals and N-benzylaniline (68T2193). Competitive fragmentation to give N-(benzylidene)aniline and phenylcarbene, which is trapped as the alkyl benzyl ether, also appears to occur. 

Stereoselectivity in the condensation reaction of 2-arylethylamines with carbonyl compounds to give 1,2,3,4-tetrahydroisoquinoline derivatives was somewhat dependent on whether acid catalysis or superacid catalysis was invoked. Particularly in the cases of 2-alkyl-N-benzylidene-2-phenethylamines, an enhanced stereoselectivity was observed with trifluorosulfonic acid (TFSA) as compared with the weaker acid, trifluoroacetic acid (TFA). Compound 43 was cyclized in the presence of TFA to give modest to good transicis product ratios. The analogous compound 44 was cyclized in the presence of TFSA to give slightly improved transicis product ratios. 

In 212 cc of water are mixed 21.2 grams (0.112 mol) of N-(benzylidene)-3-amino-2-oxa-zolidone, 8.93 grams of concentrated sulfuric acid, and 30.1 grams (0.124 mol) of 5-ni-tro-2-furaldehyde diacetate. This mixture is heated to effect the hydrolysis of N-(benzy-lidene)-3-amino-2-oxazolidone, steam distillation of the benzaldehyde and hydrolysis of 5-nitro-2-furaldehyde diacetate. Approximately IV2 hours are required for this reaction to take place. When the bulk of the benzaldehyde has been removed, 50 cc of 99% isopropanol are added, the reaction mixture is refluxed a short time, and the crystals of N-(5-nitro-2-furfurylidene)-3-amino-2-oxazolidone are filtered from the hot suspension. The product is washed with water and isopropanol and dried a yield of 23.3 grams, 92.8% based on N-(benzylidene)-3-amino-2-oxazolidone of MP 254° to 256°C is obtained, according to U.S. Patent 2,759,931. 

Process economics dictate the recycling of the unwanted isomer. Path A in Figure A8.2 illustrates that racemisation of the D-N-benzylidene amino add amide is fadle and can be carried out under very mild reaction conditions. After removal of die benzaldehyde die D,L-amino add amide can be recyded 100% conversion to the L-amino add is theoretically possible. Another method for racemisation and recycling of the L-amino add (path B, Figure A8.2) comprises the conversion of the L-amino add into die ester in the presence of concentrated add, followed by addition of ammonia, resulting in the formation of the amide. Addition of benzaldehyde and racemisation by OH- (pH =13) gives the D,L-amino add amide. In this way 100% conversion to die D-amino add is possible. 

N-Benzylidene-benzylamine N-oxide Benzenemethanamine, N-(phenylmethylene)-, N-oxide (3376-26-9)... 

Entsprechend wird 4-Hydroxy-N-benzyliden-anilin durch Essigsaure in 4-Hydroxy-N-benzyl-acetanilid (88% d.Th.) iiberfiihrt. 

N-Diphenylmethylen- 374 N-Diphenylmethylen-O-aminocarbonyl- 612 N-[l,3-Diphenyl-propyl-(2) - 374 N-[l,3-Diphenyl-propyliden-(2)]- 374, 377, 380 N-(4-Halogen-phenyI)- 683 N-Heptyl- 375 N-Heptyl-N-acetyl- 376 N-Heptyliden- 375 N-Hcptyliden-O-acetyl- 376 0-(2-Hydroxy-athyl)-N-athoxycarbonyl- 133 N-(4-Hydroxy-phenyl)- 683 0-(2-Hydroxy-l-phenyl-athyI)-N-athoxycarbonyI-aus 0-(ci-AthoxycarbonyI-benzyl)-N-athoxycar-bonyl-hydroxylamin und Lithiumalanat 133 N-Isopropyl- 682 N-Isopropylidcn- 613 N-Methyl- 133, 682 O-Methyl-N-bcnzyliden- 377 O-Methyl-N-benzyliden- 375 0-Methyl-N-(4-chlor-benzyl)- 375 0-Methyl-N-(4-chlor-benzyliden)- 375 N-Methy -N,0-diacetyI- 682 N-(4-Methyl-phenyl)- 683 0-McthyI-N-( 1 -phenyl-athyliden)- 375 N-(4-Methylthio-phenyl)- 684 N-(4-Nitro-benzyl)- 374 N-[4-Nitro-benzyliden - 374, 377 N-(2-Nitro-phenyl)- 562 N-(4-Nitro-phenyl)- 682 N-Nitroso-N-cyclohexyl- 697 N-Octyl- 374 N-Octyl-(2)-N-acetyl- 376 N-Octyliden- 374 N-0ctyliden-(2)-0-acctyl- 376 N-(Pentafluor-phenyl)-0,N-diacetyl- 697 N-Phenyl- 474, 481, 682, 783 N-Phenylacetyl-O-benzoyl- 265 N-(l-Phenyl-athyl)- 374 N-(l-Phenyl-athyl)-N-acetyl- 376 N-(l-Phenyl-athyliden)-374, 613 N-( l-Phenyl-athyliden)-0-acetyl- 376 N-[ 1 -Phenyl-buten-( 1 )-yl-(3)-iden]- 582 N-f4-Phenyl-butyl-(2)-iden]- 581 N-Phcnyl-N,0-diacetyl- 682 N-(4-Phenylthio-phenyl)- 684 N-Propyl-N-cyclohexyl- 376 N-Propyl-N-isopropyl- 376 O-Sulfonyl- 481 N-(4-Sulfonyl-phenyI)- 683 N-(2-Vinyl-phenyl)- 698... 

L-alanylglycyl-L-cysteinyl-L-lysyl-L-asparaginyl-L-phenylalanyl-L-phenylalanyl-L-tryptophanyl-L-lysyl-L-threonyl-L-threonyl-L-cysteine 6-0-benzoyl-N-(benzyloxycarbonyl) methylamide 4,6-0-benzylidene-N-benzylidene-N-(benzyloxycarbonyl) methylamide N- (benzyloxy carbonyl) -N-(benzyloxycarbonyl)-, amide N-(benzyloxycarbonyl)-, hydrazide N-(benzyloxycarbonyl)-, methylamide N-(benzyloxycarbonyl)-, methyl ester N-(benzyloxycarbonyl)-L-alanyl-L-alanine methyl ester N-(benzyloxycarbonyl)-L-alanylglycine ethyl ester N-(benzyloxycarbonyl)glycyl-L-alanine methyl ester 3,4,6-tri-0-acetyl-2-amino-2-deoxy-N-(benzyloxycarbonyl)-, benzyl ester, hydrochloride... 

A three-component domino reaction of isobutyral-dehyde, N-benzylidene aniline and pyridine-2-thiol as nucleophile gives access to 1,2,3,4-tetrahydroquino-lines as shown by Annunziata et al..161... 

In the cases of the Af-salicylidene (46) and N-benzylidene (47) anilines (15a and 15b), there is less ambiguity arising from thermal motion. For both series of compounds it is believed, on spectroscopic grounds, that the molecules are nonplanar in solution. While there are some crystal phases known in which the molecules retain this conformation (the dihedral angle between the anilino and salicylidenimino planes being of the order of 40°), in others the molecules are definitely planar. In the case of 15a it has been found that there are marked differences in densities and in photochemical and spectroscopic properties between crystals of the two types. 

The aza-MBH model reaction of N-benzylidene-4-methylbenzenesulfonamide and methyl vinyl ketone in the presence of catalyst 166 (10mol%) furnished different yields and revalues ofthe resulting adduct (S)-l (Scheme 6.159), when using long-stored (adduct 1 78% yield 70% ee) or freshly prepared (adduct 1 12% yield 16% ee) sulfonamide starting material under otherwise identical conditions. H... 

In Obereinstimmung hiermit laflt sich der EinfluB verschieden starker Basen auf eine Mono- oder Dialkylierung von N-Benzyliden-aminosaure-estem mit unterschiedlich ak-tiven Alkylhalogeniden gezielt verwerten2. 

Mit N-Benzyliden-glycin-ethylester wird fur (R)-Phenylalanin eine analoge Synthese mit 89,9 % e. e. be-schrieben Jintai Chen, Yaohnan Chen u. Huaiyu Sheng, Youji Huaxne 8, 164(1988) C. A. 110. 24259 (19889). 

Umsetzung von 1-Brom-alkanen mit N-Benzyl-hydroxylamin in Phosphorsaure-tris-[di-methylamid] (HMPT), Dehydratisierung des so gebildeten N-Alkyl-N-benzyl-hydroxyl-amins mit 2-Fluor-l-methyl-pyridinium-(4-methyl-benzolsulfonat) und saure Hydrolyse des entstandenen N-Benzyliden-amins ergibt 1-Amino-alkane in guten Ausbeuten3. 

Bei der Elektrolyse eines 1 10-Gemisches von N-Benzyliden-anilin und 1,4-Dibrom-butan in Dimethylformamid in Gegenwart von Tetrabutylammonium-jodid an einer Quecksil-ber-Kathode entsteht durch reduktive Cyclokondensation 1,2-Diphenyl-piperidin1 ... 

The asymmetric methylation of N-benzylidene-(R,S)-phenylalanine methyl ester was carried out195) in the presence of lithium salts of secondary amines derived from... 

Methoxy-7-methoxycarbonyl-1,2,3,4-tetrahydronaphthalene 2-Naphthalene-carboxylic acid, 5,6,7,8-tetrahydro-3-methoxy-, methyl ester (78112-34-2), 65, 98 Methyl acrylate (96-33-3), 66, 54, 59 dimerization by Pd(II), 66, 52 Methylamine, N-benzylidene-, 65, 140 METHYL 4-0-BENZOYL-6-BROMO-6-DEOXY-a-0-GLUCOPYRANOSIDE ... 

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