203252-06-6

Upstream product

• 922-68-9 Methyl glyoxylate 
• 104-94-9 4-methoxy-aniline 
• 147749-35-7 2-(4-methoxyphenylamino)acetic acid methyl ester 

Downstream Products

• 124156-22-5 cis-1-(4-Methoxyphenyl)-3-vinyl-4-(methoxycarbonyl)-2-azetidinone 
• 957768-51-3 methyl (2R)-4-(1,3-benzodioxol-5-yl)-2-[(4-methoxylphenyl)amino]but-3-ynoate 
• 957768-47-7 methyl (2R)-4-(2,5-dimethoxyphenyl)-2-[(4-methylphenyl)amino]but-3-ynoate 
• 957768-48-8 methyl (2R)-4-(4-tert-butylphenyl)-2-[(4-methoxyphenyl)amino]but-3-ynoate 

Relevant academic research and scientific papers

Derivatives and application to the asymmetric synthesis of unnatural α-amino acid derivative

We describe herein a manganese(IV) oxide-mediated oxidation of N-p-methoxyphenyl (PMP)-protected glycine derivatives for the synthesis of a-imino carboxylic acid derivatives. Using this methodology, utilization of unstable glyoxic acid derivatives was avoided. Furthermore, using this methodology we synthesized novel a-imino carboxylic acid derivatives such as a-imino phenyl ester, perfluoroalkyl etsers, imides, and thioester. The asymmetric Mannich reaction of those novel imine derivatives with 1,3-dicarbonyl compound is also described, and the novel a-imino imide gave improved chemical yield and stereoselectivity compared with those obtained by the use of the conventional a-imino ester-type substrate.

A convenient method for preparation of α-imino carboxylic acid derivatives and application to the asymmetric synthesis of unnatural α-amino acid derivative

We describe herein a manganese(IV) oxide-mediated oxidation of N-p-methoxyphenyl (PMP)-protected glycine derivatives for the synthesis of α-imino carboxylic acid derivatives. Using this methodology, utilization of unstable glyoxic acid derivatives was avo

Synthesis and reactivity of hexahydropyrroloquinolines

Formal [4+2] cycloaddition of cyclic enamides with imines derived from aromatic amines gave the 4-arylhexahydropyrroloquinoline skeleton in one step as mixtures of diastereoisomers. Aromatic imines derived from formaldehyde and methylglyoxalate also participated in this chemistry, with the latter favouring formation of the endo-cycloadduct. The cycloadducts derived from methylglyoxalate were unstable and fragmented to give highly substituted quinolines under both neutral and basic conditions. Imines derived from 3-cyanoacrolein also underwent cycloaddition and gave an advanced potential precursor to martinellic acid, albeit with poor diastereoselectivity.

Base-promoted isomerization of cis-4-formyl-2-azetidinones: Chemoselective C4-epimerization vs rearrangement to cyclic enaminones

Two simple, efficient, and complementary methods for the regiospecific C4-epimerization of cis-4-formyl-2-azetidinones 1-3 are described. The first method uses 40% aqueous dimethylamine as reagent in heterogeneous medium with benzene at room temperature, in the presence of benzyltributylammonium bromide (3-4 mol %) as the phase-transfer catalyst. This transformation tolerates alkyl, alkenyl, alkynyl, aryl, and alkoxy substituents at the C3 of the 2-azetidinone ring. However, limitations of this isomerization are as follows: (i) only N-(p-methoxyphenyl)-β-lactams can be used, and (ii) transformation is less compatible with heteroatomic substituents bonded to the C3 position of the 2-azetidinone ring. A highly general solution to these problems relies on the use of sodium carbonate as the isomerization reagent in different solvents. We also describe a novel base-promoted rearrangement of the β-lactam ring to cyclic enaminones 6 and 21, involving an E1cB-elimination reaction in cis-4-formyl-2-azetidinones.

Mechanism of palladium complex-catalyzed enantioselective Mannich-type reaction: Characterization of a novel binuclear palladium enolate complex

Studies on the enantioselective addition of enol silyl ethers to imines catalyzed by optically active palladium diaquo complexes 3 or binuclear palladium μ-hydroxo complex 4 are described, with particular focus on the mechanistic aspects. Asymmetric induction in the reaction using [Pd((R)-binap)(H2O)2]2+(BP4 -)2 (3a) was quite sensitive to the reaction conditions, suggesting unfavorable effects of HBF4 generated from 3a in situ. Novel optically active binuclear μ-hydroxo complexes [{Pd((R)-binap)(μ-OH)}2]2+(BF4 -)2 (4a), [{Pd-((R)-tol-binap)(μ-OH)}2]2+(BF4 -)2 (4b), [{Pd((R)-binap)(μ-OH)}2]2+(TfO-)2 (4c), and [{Pd((R)-tol-binap)(μ-OH)}2]2+(TfO-) 2 (4d) were prepared and were found to be better catalysts for the asymmetric Mannich-type reaction. Benzoylalanine derivatives 5 were obtained in excellent chemical and optical yields (up to 90% ee). Mechanistic studies using 1H NMR and electrospray ionization mass spectrometry indicated that a unique binuclear palladium-sandwiched enolate 12 was involved in the reaction of enol silyl ether 1 with imine 2 catalyzed by 4.