51212-29-4

Upstream product

• 113107-63-4 methyl 4-tert-butyldimethylsiloxy-3-phenyl-4-(phenylthio)butanonate 
• 122-78-1 phenylacetaldehyde 
• 96-32-2 bromoacetic acid methyl ester 
• 201230-82-2 carbon monoxide 
• 103-26-4 methyl cinnamate 
• 57044-58-3 (E)/(Z)-β-Trimethylsiloxystyrene 
• 40110-66-5 (E)-2-phenyl-1-(phenylsulfinyl)ethene 
• 40110-65-4 (+/-)_S-(Z)-2-phenyl-1-(phenylsulfinyl)ethene 
• 103-26-4 Methyl cinnamate 
• 106543-47-9 t-3-Phenyl-t-2-(trimethylsiloxy)-r-1-cyclopropancarbonsaeure-methylester 
• 127642-45-9 2-Phenyl-3-trimethylsilanyloxy-cyclopropanecarboxylic acid methyl ester 

Downstream Products

• 1076190-33-4 methyl 4-{[(1S)-1-(aminocarbonyl)propyl]amino}-3-phenylbutanoate 
• 112423-38-8 cis-5-allyl-4,5-dihydro-4-phenyl-2(3H)-furanone 
• 112423-35-5 trans-5-allyl-4,5-dihydro-4-phenyl-2(3H)-furanone 
• 92927-63-4 (4R^*, 5S^*)-dihydro-5-methyl-4-phenyl-2(3H)-furanone 
• 112423-41-3 cis-5-Methyl-4-phenyl-4,5-dihydro-2(3H)-furanone 
• 112423-44-6 (4R,5S)-5-Butyl-4-phenyl-dihydro-furan-2-one 
• 112423-44-6 trans-5-n-Butyl-4-phenyl-4,5-dihydro-2(3H)-furanone 
• 143585-30-2 cis-4,5-Dihydro-5-(3,3-dimethyl-2-oxobutyl)-4-phenyl-2(3H)-furanone 
• 143585-30-2 trans-4,5-Dihydro-5-(3,3-dimethyl-2-oxobutyl)-4-phenyl-2(3H)-furanone 
• 1076190-35-6 (2S)-2-(2-oxo-4-phenyl-2,5-dihydro-1H-pyrrol-1-yl)butanamide 

Relevant academic research and scientific papers

Synthesis of substituted γ- and δ-lactams through Mannich-type reactions of solid-supported N-acyliminium ions

We report the results of our recent investigations into the reactivity of cyclic solid-supported N-acyliminium ions. An intermolecular Mannich-type transformation of these intermediates was used to generate libraries of substituted lactams. Masked aldehyde building blocks were readily prepared and coupled to peptides immobilized on PEGA800(polyethylene glycol dimethyl acrylamide) resin through an HMBA [4-(hydroxymethyl)benzoic acid] linker. When treated with acid, the aldehyde was cleanly released and condensed with the amide backbone to form a hydroxylactam/N-acyliminium ion, which underwent intermolecular reactions with a series of nucleophilic heterocycles, such as substituted indoles, thiophenes, furans, and electron-rich benzenes. The resulting lactams were formed within a few minutes and in high purities (typically >85 %). A new and efficient method for the solid-phase synthesis of diversely substituted γ- and δ-lactams through Mannich-type reactions of cyclic N-acyliminium ions is presented. A wide range of external aromatic and heteroaromatic carbon nucleophiles could be successfully used in the sequence.

Enantiomerically pure bis(phosphanyl)carbaborane(12) compounds

Enantiomerically pure (RP,RP)- and (R P,SP)-1,2-bis[1-adamantyloxy-( - )-menthyloxyphosphanyl]- closo-dicarbaborane(12), 1,2-bis[bis( - )-menthyloxyphosphanyl]-closo- dicarbaborane(12) and 1,2-bis [bis (4-tert-butylphenyloxy)phosphanyl] -closo-dicarbaborane(12) were synthesised by the reaction of dilithiated l,2-dicarba-closo-dodecaborane(12) with two equivalents of the corresponding chlorophosphite. The phosphonites are stable towards epimerisation, oxygen, and water. P...P through-space coupling was observed, and the 3JPP coupling constants were determined by spectral simulation and DFT calculations. Late transition-metal complexes with molybdenum, and rhodium, were prepared to study the coordination properties of the bis(phosphanyl)carbaborane(12) compounds. Catalytic properties of various rhodium complexes were investigated in homogeneous catalytic hydroformylation reactions with, various olefins.

NEW HETEROCYCLIC DERIVATIVES USEFUL FOR THE TREATMENT OF CNS DISORDERS

The present invention relates to new compounds, processes for preparing them, pharmaceutical compositions containing them and their use as pharmaceuticals.

Highly regioselective rhodium-catalysed hydroformylation of unsaturated Esters: The first practical method for quaternary selective carbonylation

Highly regioselective hydroformylation of unsaturated esters can be achieved when a highly reactive, ligand-modified, rhodium catalyst is employed near ambient temperatures (15-50°C) and pressures over 30 bar. The use of 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phosphaadamantane shows distinct advantages over other commonly applied phosphanes in terms of reaction rate, and regio- and chemoselectivity. Hydroformylation of a range 1,1-di- and 1,1,2-trisubstituted unsaturated esters yields quaternary aldehydes that are forbidden products according to Keulemans Rule. The aldehydes can be reductively aminated with molecular hydrogen to give β-amino acid esters in high yield. The overall green chemical process involves converting terminal alkynes into unusual β-amino acid esters with only water generated as an essential byproduct. This catalytic system has also been applied to the hydroformylation of simple 1,2-disubstitued unsaturated esters, which have been hydroformylated with excellent α-selectivity and good chemo-selectivity for the first time.

Hydroformylation of cinnamic acid derivatives catalyzed by rhodium complexes

The hydroformylation of methyl cinnamate catalyzed by various rhodium complexes affords the aldehyde 1a with good chemo- and regio-selectivity, while in the case of methyl p-chlorocinnamate the predominant reaction is the substrate hydrogenation. Higher yields of the desired aldehydes 1a and 1b are obtained by hydroformylation of the cinnamaldehyde and p-chlorocinnamaldehyde diethylacetal, respectively, under the same reaction conditions. These aldehyde products are valuable drug precursors.

A Flexible Synthesis of Methyl 4-Oxobutanoates and Their Derivatives

Ring cleavage of several methyl 2-trimethylsiloxycyclopropanecarboxylates 3 provides rather sensitive methyl 4-oxobutanoates (β-formyl esters) 4 in excellent yields.Siloxycyclopropanes 3 are easily available either directly from the corresponding silyl en

Chemistry of O-Silylated Ketene Acetals. Novel Chemical Transformation of Vinyl Sulfoxides and Related Sulfoxides

It is shown that vinyl sulfoxides undergo two novel modes of reactions induced selectively by the O-silylated ketene acetal used.Vinyl sulfoxides, on treatment with bulky tert-butyldimethylsilyl ketene acetals, undergo a Michael-Pummerer-type reaction to

Catalytic Hydrogenolysis of Methyl 2-Siloxycyclopropanecarboxylates: Investigations Regarding Chemoselectivity, Regioselectivity, and Stereoselectivity

Alkyl-substituted methyl 2-(trimethylsiloxy)cyclopropanecarboxylates 8a - 8f are opened by hydrogen in the presence of palladium on carbon affording 4-oxoalkanoic esters 10a - 10e by desilylation. 2-Phenyl-substituted cyclopropanes 8g - 8j, however, provide 4-phenylbutanoic esters 13g - 13j under these conditions.Formation of 13j is not stereoselective.Here the primary cyclopropane cleavage is followed by hydrogenolysis of the benzylic C-O bond.This subsequent reaction can be suppressed in the case of 8g by poisoning the catalyst with triethylamine; otherwise the tert-butyldimethylsiloxy compounds 11g - 11i have to be used.Butanoic esters 14h and 14i, respectively, are formed as mixtures of diastereomeres, which is another indication for nonstereoselective hydrogenolysis of cyclopropanes.Whereas slow desilylation by hydrogen was observed with the 3-phenyl-substituted cyclopropane derivative 8k, the vinylcyclopropane 8m in part suffers cleavage of the 1-3 bond of the three-membered ring.Regio- and stereoselectivity of the hydrogenolysis of the donor-acceptor-substituted cyclopropanes 8 and 11 are discussed.

HYDROFORMYLATION OF OLEFINS WITH PARAFORMALDEHYDE CATALYZED BY RHODIUM COMPLEXES

The addition of formaldehyde to olefins is efficiently catalyzed by RhH2(O2COH)2 and gives the corresponding aldehydes in neutral solution.