139527-18-7

Upstream product

• 94800-94-9 5-Hydroxy-5-phenyl-pentanoic acid ethyl ester 
• 100-58-3 phenylmagnesium bromide 
• 73172-56-2 ethyl 4-benzoylbutanoate 
• 5205-39-0 ethyl glutaroyl chloride 
• 22768-07-6 (E)-ethyl 5-phenylpent-4-enoate 
• 1173997-10-8 ethyl 4-((1-phenyl-1H-tetrazol-5-yl)sulfonyl)butanoate 
• 100-52-7 benzaldehyde 

Downstream Products

• 112607-34-8 (6S) 6-phenyltetrahydro-2H-pyran-2-one 

Relevant academic research and scientific papers

Rhodium-catalyzed asymmetric hydroboration of γ,δ-unsaturated amide derivatives: δ-borylated amides

γ,δ-Unsaturated amides in which the alkene moiety bears an aryl or heteroaryl substituent undergo regioselective rhodium-catalyzed δ-borylation by pinacolborane to afford chiral secondary benzylic boronic esters. The results contrast the γ-borylation of γ,δ-unsaturated amides in which the disubstituted alkene moiety bears only alkyl substituents; the reversal in regiochemistry is coupled with a reversal in the sense of π-facial selectivity.

Asymmetric Organocatalytic One-Pot, Two-Step Sequential Process to Synthesize Chiral Acetal-Containing Polycyclic Derivatives from Cyclic Hemiacetals and Enones

We have developed an efficient one-pot, two-step sequential process to synthesize biologically and synthetically important chiral acetal-containing polycyclic derivatives. This novel protocol had been proved to proceed via Michael-lactolization-oxocarbenium ion ring-closing sequence, which was initiated by a key reactive enamine intermediate and interrupted the previously established reaction pathway of two different enones used in this work, and generated the corresponding cycloadducts with excellent stereoselectivity bearing up to seven continuous stereocenters. Both chiral and racemic starting cyclic hemiacetals worked well in this strategy. The synthetic applications of the obtained polycyclic products have also been demonstrated.

Stereodivergent preparation of valuable γ- Or δ-hydroxy esters and lactones through one-pot cascade or tandem chemoenzymatic protocols

A series of enantiopure hydroxy esters and lactones has been synthesized in a chemodivergent manner via alcohol dehydrogenase (ADH) reduction of the corresponding keto esters by means of cascade or tandem protocols. Thus, ADH from Rhodococcus ruber (ADH-A) or Lactobacillus brevis (LBADH) afforded both antipodes in a very selective way when dealing with small derivatives. With bulkier substrates, ADH from Ralstonia sp. (RasADH) was successfully employed to achieve the synthesis of enantioenriched γ- or δ-hydroxy esters. To isolate the corresponding lactones, two different approaches were followed: a cascade reaction by spontaneous cyclization of the hydroxy ester intermediate, or a one-pot two-step tandem protocol. Moreover, a chemoenzymatic route was designed to obtain a chiral brominated lactone, which enabled further modifications in a sequential fashion by Pd-catalyzed reactions, affording relevant functionalized lactones.

Remote ester group leads to efficient kinetic resolution of racemic aliphatic alcohols via asymmetric hydrogenation

A highly efficient method for kinetic resolution of racemic aliphatic alcohols without conversion of the hydroxyl group has been realized; the method involves hydrogenation mediated by a remote ester group and is catalyzed by a chiral iridium complex. This powerful, environmentally friendly method provides chiral δ-alkyl-δ-hydroxy esters and δ-alkyl-1,5-diols in good yields with high enantioselectivities even at extremely low catalyst loading (0.001 mol %).

Catalytic asymmetric hydrogenation of δ-ketoesters: Highly efficient approach to chiral 1,5-diols

High turnover: An highly efficient catalytic asymmetric hydrogenation of δ-aryl-δ-ketoesters has been realized by using the chiral spiroiridium catalyst (R)-1. Chiral 1,5-diol products are obtained with excellent enantioselectivity and turnover numbers (TONs) as high as 100 000. TOF=turnover frequency. Copyright

Selective reductions. 59. Effective intramolecular asymmetric reductions of α-, β-, and γ-keto acids with diisopinocampheylborane and intermolecular asymmetric reductions of the corresponding esters with B-chlorodiisopinocampheylborane

A comparison of the stereochemistry of the products obtained from the intramolecular asymmetric reduction of a series of keto acids with (-)-diisopinocampheylborane and intermolecular asymmetric reduction of the corresponding series of keto esters with (-)-B-chlorodiisopinocampheylborane ((-)-DIP-Chloride) has been made. The stereochemistry of the hydroxy acids from the reduction of keto acids is dependent only on the enantiomer of the reagent used. The stereochemistry of the products from the reduction of keto esters is also consistent, except those of aliphatic α-keto esters. α-, β-, and γ-keto acids provide the corresponding hydroxy acids in 77-98% ee, and the α- and γ-keto esters afford the hydroxy esters in 82-≥99% ee. β-Keto esters do not undergo reduction. Although the reduction of δ-keto acids does not proceed under the same reaction conditions, the reduction of δ-keto esters is facile. All of the products from the reduction of γ-keto acids and esters and δ-keto esters were converted to the corresponding lactones. This study revealed that DIP-Chloride is an efficient reagent for the reduction of α-keto esters at low temperatures.

Preparation of Functionalized Dialkylzinc Reagents via an Iodine-Zinc Exchange Reaction. Highly Enantioselective Synthesis of Functionalized Secondary Alcohols

Functionalized dialkylzincs are obtained by the reaction of polyfunctional alkyl iodides with Et2Zn in excellent yield.Their treatment with aldehydes, in the presence of the titanium catalyst 6, affords functionalized secondary alcohols with high enantios