N-Diphenylmethylen-

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... 

Diastereomeric excesses of up 56% have been claimed for the preparation of a-amino-P-hydroxy acids via the aldol condensation of aldehydes with f-butyl N-(diphenylmethylene)glycinate [63]. It might be expected that there would be thermodynamic control of the C-C bond formation influenced by the steric requirements of the substituents, but the use of cinchoninium and cinchonidinium salts lead to essentially the same diastereoselectivity. The failure of both tetra-n-butylammo-nium and benzyltriethylammonium chloride to catalyse the reaction is curious. 

Die Spaltung von Iminen zu Aminen (s.Bd. XI/1, S. 955) kann unter anderem mit Oxal-saure in Ether/95% Ethanol vorgenommen werden man erhalt dabei die kristallisierenden Oxalate der Amine (genauer Aminium-hydrogenoxalate), wie hier fiir die Spaltung von allenischen N-Diphenylmethylen-aminen gezeigt1. 

On the other hand, the synthesis of Shih and Bayley is based on the C -alkylation of ethyl N-(diphenylmethylene)glycinate by 3-[4-(iodomethyl)phenyl]-3-(trifluoromethyl)-3//-diazirine (57) (Scheme 13). The precursor for the diazirine-containing alkylating reagent is the O-protected benzyl alcohol 53J1251... 

In 1999, in consideration of the readily structural modifications and fine-tuning of catalysts to attain sufficient reactivity and selectivity, Maruoka and coworkers designed and prepared the structurally rigid, chiral spiro ammonium salts of type 1 derived from commercially available (S)- or (R)-1,1 -bi-2-naphthol as a new C2-symmetric chiral phase-transfer catalyst, and successfully applied this to the highly efficient, catalytic enantioselective alkylation of N-(diphenylmethylene)glycine tert-butyl ester under mild phase-transfer conditions (Scheme 5.1) [7]. 

With bis(3,4,5-trifluorophenyl)-substituted catalyst (S)-16A, the substituent effect of R was examined by changing the number of straight alkyl chains (Figure 5.1). In the asymmetric benzylation of N-(diphenylmethylene)glycine tert-butyl ester 2, use of (CH3(CH2) ,1)2NH (n > 4) gave a uniformly high asymmetric induction. 

Scheme 8 Asymmetric alkylation of N-(diphenylmethylene)glycine isopropyl ester with benzyl bromide catalyzed by the dendronized catalysts shown in Fig. 25...

Nucleophiles A, dibenzylamine, B, sodium diethyl malonate, C, lithium salt of tert-butyl N-(diphenylmethylene)glycinate. 

Also treatment of N-diphenylmethylene-jS-hydroxyamino acid methyl ester 692 with di-isopropylcarbodiimide in the presence of CuCl achieves formation of the -didehydro amino acid esters 693. ... 

Related Reagents. l-Benzoyl-2-r-butyl-3,5-dimethyl-4-imi-dazolidinone (2S,4S)-3-Benzoyl-2-/-butyl-4-methyl-1,3-oxazo-lidin-5-one N-Benzyloxycarbonyl-t-serine p-Lactone N-r-Buto-xycarbonyl-N-methylaminomethyllithium (R)-2-r-Butyl-6-methyl-4H-l, 3-dioxin-4-one N, N-Diethylaminoacetonitrile Ethyl N-(Diphenylmethylene)glycinate Ethyl Isocyanoacetate Methyl ot-Phenylglycinate... 

Cinchonanium, l-(9-anthracenylmethyl)-9-(2-propenyloxy)-, bromide, (8a,9R)-and L-Glutamic acid, N-(diphenylmethylene)-, l-(l,l-dimethylethyl) 5-methyl... 

N-(Diphenylmethylene)glycine tert-butyl ester was purchased from the Aldrich Chemical Co., Inc. and used as received. 

C17H17N02 ethyl N- diphenylmethylene)glycinate 69555-14-2 25.00 1.1411 2 30216 C17H23N06 boc-L-glutamic acid 5-benzylester 13574-13-5 25.00 1.1888 2... 

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