112607-27-9

Upstream product

• 66661-69-6 2-Phenylmaleinaldehydsaeure-ethylester 
• 121925-53-9 4-ethoxy-4-oxo-2-phenylbutanoic acid 
• 51425-66-2 (4,5-dihydro-2-furanyloxy)(trimethyl)silane 
• 17763-67-6 Phenyl triflate 
• 6836-98-2 3-phenyldihydrofuran-2-one 
• 1131-15-3 2-phenylsuccinic anhydride 
• 879098-62-1 (2R,3R)-2-{(+)-isomenthoxy}-3-phenyl-1-oxacyclopentane 

Downstream Products

• 6837-05-4 (+/-)-2-phenyl-1,4-butanediol 

Relevant academic research and scientific papers

Catalytic, Enantioselective β-Protonation through a Cooperative Activation Strategy

The NHC-catalyzed transformation of unsaturated aldehydes into saturated esters through an organocatalytic homoenolate process has been thoroughly studied. Leveraging a unique “Umpolung”-mediated β-protonation, this process has evolved from a test bed for homoenolate reactivity to a broader platform for asymmetric catalysis. Inspired by our success in using the β-protonation process to generate enals from ynals with good E/Z selectivity, our early studies found that an asymmetric variation of this reaction was not only feasible, but also adaptable to a kinetic resolution of secondary alcohols through NHC-catalyzed acylation. In-depth analysis of this process determined that careful catalyst and solvent pairing is critical for optimal yield and selectivity; proper choice of nonpolar solvent provided improved yield through suppression of an oxidative side reaction, while employment of a cooperative catalytic approach through inclusion of a hydrogen bond donor cocatalyst significantly improved enantioselectivity.

Accessing non-natural reactivity by irradiating nicotinamide-dependent enzymes with light

Enzymes are ideal for use in asymmetric catalysis by the chemical industry, because their chemical compositions can be tailored to a specific substrate and selectivity pattern while providing efficiencies and selectivities that surpass those of classical synthetic methods. However, enzymes are limited to reactions that are found in nature and, as such, facilitate fewer types of transformation than do other forms of catalysis. Thus, a longstanding challenge in the field of biologically mediated catalysis has been to develop enzymes with new catalytic functions. Here we describe a method for achieving catalytic promiscuity that uses the photoexcited state of nicotinamide co-factors (molecules that assist enzyme-mediated catalysis). Under irradiation with visible light, the nicotinamide-dependent enzyme known as ketoreductase can be transformed from a carbonyl reductase into an initiator of radical species and a chiral source of hydrogen atoms. We demonstrate this new reactivity through a highly enantioselective radical dehalogenation of lactones - a challenging transformation for small-molecule catalysts. Mechanistic experiments support the theory that a radical species acts as an intermediate in this reaction, with NADH and NADPH (the reduced forms of nicotinamide adenine nucleotide and nicotinamide adenine dinucleotide phosphate, respectively) serving as both a photoreductant and the source of hydrogen atoms. To our knowledge, this method represents the first example of photo-induced enzyme promiscuity, and highlights the potential for accessing new reactivity from existing enzymes simply by using the excited states of common biological co-factors. This represents a departure from existing light-driven biocatalytic techniques, which are typically explored in the context of co-factor regeneration.

Enantioselective β-Protonation by a Cooperative Catalysis Strategy

An enantioselective N-heterocyclic carbene (NHC)-catalyzed β-protonation through the orchestration of three distinct organocatalysts has been developed. This cooperative catalyst system enhances both yield and selectivity, compared to only the NHC-catalyz

Weak arene C-h×××o hydrogen bonding in palladium-catalyzed arylation and vinylation of lactones

Weak force in action: In the title reaction, the palladium catalyst (see figure, left) uses weak CH×××O hydrogen bonding to control the absolute configuration of the new stereocenter. A similar palladium catalyst (right) used conventional NH×××O hydrogen bonding to guide stereoselection. Copyright

Catalytic hydrogenation of carboxamides and esters by well-defined Cp*Ru complexes bearing a protic amine ligand

A novel catalytic method for the straightforward hydrogenation of carboxamides and esters to primary alcohols has been developed. Chiral modification in the ligand sphere of the well-defined Cp*Ru catalyst molecule opens up a new possibility for the development of an enantioselective hydrogenation of racemic substrates via dynamic kinetic resolution.

Cobalt(diamine)-catalyzed cross-coupling reaction of alkyl halides with arylmagnesium reagents: Stereoselective constructions of arylated asymmetric carbons and application to total synthesis of AH13205

A cobalt-diamine complex catalyzes the cross-coupling reactions of primary and secondary alkyl halides with aryl Grignard reagents. It is confirmed that oxidative addition of alkyl halide to cobalt proceeds via a radical process. Optically pure Ueno-Stork halo acetals undergo diastereoselective cross-coupling reactions, the products of which are transformed into optically active THF derivatives. A sequential radical cyclization/arylation reaction under cobalt catalysis provides extremely short access to a synthetic prostaglandin AH13205.

Stereoselective Protonation of Carbanions, 6. Enantioselective Protonation of γ-Butyrolactone Enolates

The lithium enolates 3Li-7Li, produced from 3-7 by LDA or LiHMDS in THF, are protonated with eleven chiral proton sources at -78 deg C in THF which produced high enantioselectivities with 1Li and 2Li.Although th