143329-84-4

Upstream product

• 143329-81-1 α,α'-dimethyl-1,3-benzenedimethanol 
• 108-24-7 acetic anhydride 
• 876-27-7 4-chlorophenyl acetate 
• 108-22-5 Isopropenyl acetate 
• 6781-42-6 1,3-diacetylbenzene 
• 141-78-6 ethyl acetate 

Downstream Products

• 6781-44-8 (R,R)-α,α'-dimethyl-1,3-benzenedimethanol 

Relevant academic research and scientific papers

Asymmetric Chemoenzymatic Reductive Acylation of Ketones by a Combined Iron-Catalyzed Hydrogenation–Racemization and Enzymatic Resolution Cascade

A general and practical process for the conversion of prochiral ketones into the corresponding chiral acetates has been realized. An iron carbonyl complex is reported to catalyze the hydrogenation–dehydrogenation–hydrogenation of prochiral ketones. By merging the iron-catalyzed redox reactions with enantioselective enzymatic acylations a wide range of benzylic, aliphatic and (hetero)aromatic ketones, as well as diketones, were reductively acylated. The corresponding products were isolated with high yields and enantioselectivities. The use of an iron catalyst together with molecular hydrogen as the hydrogen donor and readily available ethyl acetate as acyl donor make this cascade process highly interesting in terms of both economic value and environmental credentials.

Aminocyclopentadienyl Ruthenium Complexes as Racemization Catalysts for Dynamic Kinetic Resolution of Secondary Alcohols at Ambient Temperature

Aminocyclopentadienyl ruthenium complexes, which can be used as room-temperature racemization catalysts with lipases in the dynamic kinetic resolution (DKR) of secondary alcohols, were synthesized from cyclopenta-2,4-dienimines, Ru3(CO)12, and CHCl 3: [2,3,4,5-Ph4(η5-C 4CNHR)]Ru-(CO)2Cl (4: R = i-Pr; 5: R = n-Pr; 6: R = t-Bu), [2,5-Me2-3,4-Ph2(η5-C 4CNHR)]Ru(CO)2Cl (7: R = i-Pr; 8: R = Ph), and [2,3,4,5-Ph4(η5-C4CNHAr)]Ru(CO) 2Cl (9: Ar =p-NO2C6H4; 10: Ar = p-ClC6H4; 11: Ar = Ph; 12: Ar = p-OMeC6H 4; 13: Ar = p-NMe2C6H4). The tests in the racemization of (S)-4-phenyl-2-butanol showed that 7 is the most active catalyst, although the difference decreased in the DKR. Complex 4 was used in the DKR of various alcohols; at room temperature, not only simple alcohols but also functionalized ones such as allylic alcohols, alkynyl alcohols, diols, hydroxyl esters, and chlorohydrins were successfully transformed to chiral acetates. In mechanistic studies for the catalytic racemization, ruthenium hydride 14 appeared to be a key species. It was the major organometallic species in the racemization of (S)-1-phenylethanol with 4 and potassium tert-butoxide. In a separate experiment, (S)-1-phenylethanol was racemized catalytically by 14 in the presence of acetophenone.

Dynamic Kinetic Resolution of Secondary Diols via Coupled Ruthenium and Enzyme Catalysis

Enzymatic acylation of secondary symmetrical diols (as meso/dl mixtures) in combination with ruthenium-catalyzed isomerization of the diol led to efficient dynamic kinetic resolution. In this way, a meso/dl mixture of the diol was transformed to enantiomerically pure (R,R)-diacetate, making efficient use of all the diol material. For some of the flexible substrates, substantial amounts of meso-diacetates were formed as side products. The results indicate that the major part of the meso product is formed via an intramolecular acyl-transfer pathway.

Separation of Remote Diol and Triol Stereoisomers by Enzyme-Catalyzed Esterification in Organic Media or Hydrolysis in Aqueous Media

The separation of symmetric, remote, secondary diol stereoisomers by stereoselective enzyme-catalyzed acetylation with acetic anhydride in anhydrous, low polarity organic solvents or by stereoselective enzyme-catalyzed hydrolysis of the corresponding pera