172424-27-0

Basic information

• Product Name: Benzenemethanol, a-methyl-4-(trifluoromethyl)-, acetate, (R)-
• CAS NO: 172424-27-0
• Molecular Formula: C11H11F3O2
• Molecular Weight: 232.202
• Mol File: 172424-27-0.mol

Chemical Properties

• CAS DataBase Reference: Benzenemethanol, a-methyl-4-(trifluoromethyl)-, acetate, (R)-(CAS DataBase Reference)
• NIST Chemistry Reference: Benzenemethanol, a-methyl-4-(trifluoromethyl)-, acetate, (R)-(172424-27-0)
• EPA Substance Registry System: Benzenemethanol, a-methyl-4-(trifluoromethyl)-, acetate, (R)-(172424-27-0)

Safety Data

• Hazardous Substances Data: 172424-27-0(Hazardous Substances Data)

Upstream product

• 108-22-5 Isopropenyl acetate 
• 1737-26-4 1-(4-trifluorophenyl)ethanol 
• 876-27-7 4-chlorophenyl acetate 
• 122-79-2 Phenyl acetate 
• 108-24-7 acetic anhydride 
• 709-63-7 1-(4-trifluoromethylphenyl)ethanone 
• 141-78-6 ethyl acetate 
• 108-05-4 vinyl acetate 

Downstream Products

• 1737-26-4 (R)-1-[4-(trifluoromethyl)phenyl]ethan-1-ol 

Relevant articles and documents

PQXdpap: Helical Poly(quinoxaline-2,3-diyl)s Bearing 4-(Dipropylamino)pyridin-3-yl Pendants as Chirality-Switchable Nucleophilic Catalysts for the Kinetic Resolution of Secondary Alcohols

Helically chiral poly(quinoxaline-2,3-diyl)s bearing 4-(dipropylamino)pyridin-3-yl pendants at the 5-position of the quinoxaline ring (PQXdpap) exhibited high catalytic activities and moderate to high selectivities (up to s = 87) in the acylative kinetic resolution of secondary alcohols. The solvent-dependent helical chirality switching of PQXdpap between pure toluene and a 1:1 mixture of toluene and 1,1,2-trichloroethane enabled the preparation of either compound of a pair of enantiomerically pure alcohols (>99% ee) from a single catalyst.

Chemoenzymatic Dynamic Kinetic Resolution of Secondary Alcohols Using an Air- and Moisture-Stable Iron Racemization Catalyst

Herein, we report on a metalloenzymatic dynamic kinetic resolution of sec-alcohols employing an iron-based racemization catalyst together with a lipase. The iron catalyst was evaluated in racemization and then used in dynamic kinetic resolution of a numbe

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.

Merging Iron Catalysis and Biocatalysis—Iron Carbonyl Complexes as Efficient Hydrogen Autotransfer Catalysts in Dynamic Kinetic Resolutions

A dual catalytic iron/lipase system has been developed and applied in the dynamic kinetic resolution of benzylic and aliphatic secondary alcohols. A detailed study of the Kn?lker-type iron complexes demonstrated the hydrogen autotransfer of alcohols to proceed under mild reaction conditions and allowed the combination with the enzymatic resolution. Different racemic alcohols were efficiently converted to chiral acetates in good yields and with excellent enantioselectivities.

Ligand effect in racemization and dynamic kinetic resolution of alcohols: Mechanism on cymene ruthenium complexes

A family of ruthenium complexes with different ligands was utilized in racemization of (R)-1-phenylethanol to investigate the potential influence of the ligands coordinated to the ruthenium center. Kinetic experiments showed that 16-electron cymene ruthenium complex with two chloro-bridge bonds and 18-electron ones with easily dissociative ligands are highly active for catalytic racemization of alcohols. Possible racemization mechanism for cymene ruthenium complexes was then proposed. Computational analysis of dissociation energy barrier, NBO analysis and reaction potential energy surface suggest that ligand-dissociation process is the vital step of the racemization catalyzed by cymene ruthenium complexes. Thereafter, these complexes were applied in the DKR of secondary alcohols to verify their efficiency and applicability.

A Cationic Ruthenium Complex for the Dynamic Kinetic Resolution of Secondary Alcohols

A synthetic protocol making use of a well-defined cationic ruthenium complex 2 enabling the racemization of enantiomerically pure secondary alcohols in the presence of a weak base (K2CO3) is described. The compatibility of 2 with Candida Antarctica lipase B (Novozym 435) allows the development of an efficient dynamic kinetic resolution of sec-alcohols in the absence of an additional strong base. This procedure involves the first example of a dynamic kinetic resolution of alcohols in the presence of a cationic ruthenium catalyst. In addition, we describe the conversion of ketones to the enantioenriched acetates in a one-pot reaction, probing the versatility of complex 2.

Dynamic kinetic resolution of a wide range of secondary alcohols: Cooperation of dicarbonylchlorido(pentabenzylcyclopentadienyl)ruthenium and CAL-B

The substrate scope in the dynamic kinetic resolution ofsecondary alcohols was studied by using 31 structurallydifferent alcohols and isopropenyl acetate in the presence ofdicarbonylchlorido(pentabenzylcyclopentadienyl)rutheniumand Candida antarctica lipase B (Novozym 435, CAL-B) in toluene. The enzyme and the ruthenium complex were shown to function in a highly compatible manner allowing the conversion of the racemic alcohols into the (R)-acetates in practically theoretical yields and, in most cases, ee values exceeding 99%. The results are fully comparable to those published previously by using earlier reported, state-of-the-art ruthenium-based catalysts for the alcohol racemization. A clear benefit of the dicarbonylchlorido(pentabenzylcyclopentadienyl)ruthenium system, when compared to other (cyclopentadienyl)ruthenium racemization catalysts, is its simple and cost-efficient preparation. The substrate scope of 31 secondary alcohols was studied in the dynamic kinetic resolution by utilizing dicarbonylchlorido(pentabenzylcyclopentadienyl)rutheniumand Candida antarctica lipase B (CAL-B) in the acylation with isopropenyl acetate in toluene at room temperature. The secondary alcohols were transformed into highly enantiopure (R)-acetates (in most cases ee > 99%) in close to quantitative isolatedyields. Copyright

High-yielding metalloenzymatic dynamic kinetic resolution of fluorinated aryl alcohols

Dynamic kinetic resolution (DKR) of various fluorinated aryl alcohols by a combination of lipase-catalyzed enzymatic resolution with in situ ruthenium-catalyzed alcohol racemization is described. (R)-Selective Candida antarctica lipase B (CALB) was employed for transesterification of different fluoroaryl alcohols in DKR reactions delivering the corresponding acetates in high yield (≥97%) with excellent enantiomeric excess (≥98%).

Asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens

A new asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens has been found. Although alcohols are not the natural substrates for this enzyme, a high R enantioselectivity was observed. Stereochemical studies showed that variations in substrate structure lead to strong variations in enantioselectivity. The highest enantioselectivities are obtained when the β-carbon of the secondary alcohol is tertiary or quaternary.

Combined ruthenium(II) and lipase catalysis for efficient dynamic kinetic resolution of secondary alcohols. Insight into the racemization mechanism

Pentaphenylcyclopentadienyl ruthenium complexes (3) are excellent catalysts for the racemization of secondary alcohols at ambient temperature. The combination of this process with enzymatic resolution of the alcohols results in a highly efficient synthesis of enantiomerically pure acetates at room temperature with short reaction times for most substrates. This new reaction was applied to a wide range of functionalized alcohols including heteroaromatic alcohols, and for many of the latter, enantiopure acetates were efficiently prepared for the first time via dynamic kinetic resolution (DKR). Different substituted cyclopentadienyl ruthenium complexes were prepared and studied as catalysts for racemization of alcohols. Pentaaryl-substituted cyclopentadienyl complexes were found to be highly efficient catalysts for the racemization. Substitution of one of the aryl groups by an alkyl group considerably slows down the racemization process. A study of the racemization of (S)-1-phenylethanol catalyzed by ruthenium hydride η5-Ph5CpRu(CO) 2H (8) indicates that the racemization takes place within the coordination sphere of the ruthenium catalyst. This conclusion was supported by the lack of ketone exchange in the racemization of (S)-1-phenylethanol performed in the presence of p-tolyl methyl ketone (1 equiv), which gave 1% of 1-(p-tolyl)ethanol. The structures of ruthenium chloride and iodide complexes 3a and 3c and of ruthenium hydride complex 8 were confirmed by X-ray analysis.