28541-02-8

Upstream product

• 100-52-7 benzaldehyde 
• 52267-51-3 benzyl diazoacetate 
• 126191-07-9 2-diazo-3-phenylpropanoic acid benzyl ester 
• 140-10-3 (E)-3-phenylacrylic acid 
• 103-41-3 (E)-cinnamic acid benzyl ester 
• 102-92-1 Cinnamoyl chloride 
• 2579-22-8 Phenylpropargyl aldehyde 
• 15097-38-8 (carbobenzyloxymethylene)triphenylphosphorane 
• 100-51-6 benzyl alcohol 
• 637-44-5 phenylpropyolic acid 
• 63888-21-1 benzyl 3-phenyl-2-propynoate 

Relevant academic research and scientific papers

Donor-acceptor fluorophores as efficient energy transfer photocatalysts for [2 + 2] photodimerization

Mild [2 + 2] photodimerization of enone substrates was induced by donor-acceptor fluorophores. Enone substrates were activated efficiently for anti-head to head dimerizations with a high yield (up to 83%) and high selectivity. The adjustable excited state potential also allows donor-acceptor fluorophores to be used for isomerization of the above substrates, confirming the potential of donor-acceptor fluorophores as energy transfer photocatalysts.

Carbocation Lewis Acid TrBF4-Catalyzed 1,2-Hydride Migration: Approaches to (Z)-α,β-Unsaturated Esters and α-Branched β-Ketocarbonyls

Carbocation Lewis acid TrBF4-catalyzed 1,2-hydride migration of α-alkyldiazoacetates themselves or in situ-generated cross-coupling adducts of aldehydes and α-alkyldiazoacetates has been developed, affording (Z)-α,β-unsaturated esters and α-branched β-ketocarbonyls, respectively, in good yields and with high regioselectivities.

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.

MYOGLOBIN-BASED CATALYSTS FOR CARBENE TRANSFER REACTIONS

Methods are provided for carrying out carbene transfer transformations such as olefin cyclopropanation reactions, carbene heteroatom-H insertion reactions (heteroatom = N, S, Si), sigmatropic rearrangement reactions, and aldehyde olefination reactions with high efficiency and selectivity by using a novel class of myoglobin-based biocatalysts. These methods are useful for the synthesis of a variety of organic compounds which contain one or more new carbon-carbon or carbon-heteroatom (N, S, or Si) bond. The methods can be applied for conducting these transformations in vitro (i.e., using the biocatalyst in isolated form) and in vivo (i.e., using the biocatalyst in a whole cell system).

Myoglobin-catalyzed olefination of aldehydes

The olefination of aldehydes constitutes a most valuable and widely adopted strategy for constructing carbon-carbon double bonds in organic chemistry. While various synthetic methods have been made available for this purpose, no biocatalysts are known to mediate this transformation. Reported herein is that engineered myoglobin variants can catalyze the olefination of aldehydes in the presence of α-diazoesters with high catalytic efficiency (up to 4,900 turnovers) and excellent Ediastereoselectivity (92-99.9 % de). This transformation could be applied to the olefination of a variety of substituted benzaldehydes and heteroaromatic aldehydes, also in combination with different alkyl α-diazoacetate reagents. This work provides a first example of biocatalytic aldehyde olefination and extends the spectrum of synthetically valuable chemical transformations accessible using metalloprotein-based catalysts.

Ruthenium-catalyzed, one-pot alcohol oxidation-wittig reaction producing αβ unsaturated esters

By a one-pot process, αβ-unsaturated esters were synthesized in high yield through the Ru-catalyzed oxidation of primary alcohols and the coupling of the resulting aldehydes and stabilized Wittig reagents. The ruthenium catalyst is composed of ruthenium nanoparticles embedded in aluminum oxyhydroxide and can be recovered simply by filtration or decantation. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009.