76403-50-4

Upstream product

• 76403-24-2 (1-Isocyanato-3-methyl-but-3-enyl)-benzene 
• 76403-34-4 (3-Methyl-1-phenyl-but-3-enyl)-carbamic acid methyl ester 
• 76403-40-2 (4-Hydroxy-3-methyl-1-phenyl-butyl)-carbamic acid methyl ester 
• 1949-41-3 2-methyl-4-phenylbutanoic acid 
• 242483-39-2 2-methyl-4-phenyl-butyryl chloride 
• 117341-58-9 5,6-Dihydro-6-methoxy-5-methylene-3-phenyl-4H-1,2-oxazine 
• 117341-61-4 6-Methoxy-5-methyl-3-phenyl-6H-1,2-oxazine 
• 76403-46-8 (3S,5R)-3-Methyl-2-oxo-5-phenyl-pyrrolidine-1-carboxylic acid methyl ester 
• 86791-05-1 N-hydroxy-2-methyl-4-phenylbutyramide 
• 38795-58-3 2-methyl-4-phenylbutyric acid methyl ester 

Relevant academic research and scientific papers

Synthetic Utility of N-Benzoyloxyamides as an Alternative Precursor of Acylnitrenoids for γ-Lactam Formation

Described herein is the development of a new entry of acylnitrenoid precursors for γ-lactam synthesis via an intramolecular C-H amidation reaction. Upon Ir catalysis, N-benzoyloxyamides serve as efficient substrates to afford 5-membered amides. Mechanistic studies revealed that the generation of a putative Ir-carbonylnitrenoid via N-O bond cleavage is facilitated by the chelation of countercations. This protocol offers a convenient and step-economic route to γ-lactams starting from the corresponding carboxylic acids.

Ruthenium(II)-Catalyzed Enantioselective γ-Lactams Formation by Intramolecular C-H Amidation of 1,4,2-Dioxazol-5-ones

We report the Ru-catalyzed enantioselective annulation of 1,4,2-dioxazol-5-ones to furnish γ-lactams in up to 97% yield and 98% ee via intramolecular carbonylnitrene C - H insertion. By employing chiral diphenylethylene diamine (dpen) as ligands bearing electron-withdrawing arylsulfonyl substituents, the reactions occur with remarkable chemo- and enantioselectivities; the competing Curtius-type rearrangement was largely suppressed. Enantioselective nitrene insertion to allylic/propargylic C - H bonds was also achieved with remarkable tolerance to the C=C and C=C bonds.

Ruthenium(II)-Catalyzed Enantioselective ?-Lactams Formation by Intramolecular C-H Amidation of 1,4,2-Dioxazol-5-Ones

We report the Ru-Catalyzed enantioselective annulation of 1,4,2-Dioxazol-5-Ones to furnish ?-Lactams in up to 97% yield and 98% ee via intramolecular carbonylnitrene C-H insertion. By employing chiral diphenylethylene diamine (dpen) as ligands bearing electron-Withdrawing arylsulfonyl substituents, the reactions occur with remarkable chemo- A nd enantioselectivities; the competing Curtius-Type rearrangement was largely suppressed. Enantioselective nitrene insertion to allylic/propargylic C-H bonds was also achieved with remarkable tolerance to the Ca?C and Ca‰iC bonds.

Selective formation of γ-lactams via C-H amidation enabled by tailored iridium catalysts

Intramolecular insertion of met al nitrenes into carbon-hydrogen bonds to form γ-lactam rings has traditionally been hindered by competing isocyanate formation. We report the application of theory and mechanism studies to optimize a class of pentamethylcyclopentadienyl iridium(III) catalysts for suppression of this competing pathway. Modulation of the stereoelectronic properties of the auxiliary bidentate ligands to be more electron-donating was suggested by density functional theory calculations to lower the C-H insertion barrier favoring the desired reaction. These catalysts transform a wide range of 1,4,2-dioxazol-5-ones, carbonylnitrene precursors easily accessible from carboxylic acids, into the corresponding γ-lactams via sp3 and sp2 C-H amidation with exceptional selectivity. The power of this method was further demonstrated by the successful late-stage functionalization of amino acid derivatives and other bioactive molecules.

Stereoselective alkylation of N-Boc-2-pyrrolidinones and N-Boc-2- piperidinones. Synthesis and characterization of disubstituted lactams

Alkylation of enolates of monosubstituted N-Boc lactams 4-6 afforded trans-disubstituted lactams as the major isomer. In the pyrrolidinone series, 1,3-induction seems to be ruled by steric interactions and the diastereoselection is low for the alkylation of enolates with small substituents at C-5 (e.g., Me) and methyl iodide. The trans selectivity improves with bulkier substituents at C-2 and/or bulkier electrophiles. The formation of 3,6-trans-disubstituted piperidinones benefits from the axial orientation of the substituent at C-2 due to the A strain with the N-Boc group and excellent trans preference is observed even in the alkylation of the lithium enolate of N-Boc-6-methyl piperidinone with methyl iodide.

Model Studies of the Reduction of 3-Phenyl-6H-1,2-oxazines, Chemo- and Stereoselectivity: Synthesis of Amino Alcohols, Amino Acids, and Related Compounds

While palladium-catalyzed hydrogenation of 3-phenyl-6H-1,2-oxazine 1 produces primary amine 5 in a nitrogen-transposition reaction, the reductions of the related 1,2-oxazines 2, 10, and the 1,2-oxazin-6-one 3 afford the expected amino alcohols 4, 11, and the γ-amino acid 6, respectively, with low diastereoselectivities.In the presence of acetic acid 3 is reductively converted into γ-keto carboxylic acid 9 and 1 into the γ-lactam derivative 12 probably by a ring contraction to a nitrone intermediate.Raney nickel as the catalyst is able to transform 1,2-oxazine 7 bearing an exo-methylene unit into 3,4-dihydro-2H-pyrrole 13.The reaction of 6H-1,2-oxazine 1 with aluminium amalgam produces pyrrole 14 in moderate yield.Treatment of 1 with sodium in 2-propanol brings about its transformation into pyrrolidine derivative 15 together with pyrrole 14 and amino alcohol 4 as minor products.The chemoselectivity and stereoselectivity of these reductions are discussed including mechanistic proposals for the multistep processes involved. Key Words: 1,2-Oxazines / Hydrogenation, catalytic / Amino alcohols / γ-Amino acids / Pyrroles / γ-Lactams

An Efficient and General Synthesis of 5-Substituted Pyrrolidinones

2-Pyrrolidinone derivatives are widespread materials of considerable laboratory and commercial importance.In spite of this, there is no generally useful synthesis of either symmetrically or unsymmetrically 5,5-disubstituted derivatives.This is particularl