75853-10-0Relevant academic research and scientific papers
Zr(OBut)4 as an effective promoter for the Meerwein-Ponndorf-Verley alkynylation and cyanation of aldehydes: Development of new asymmetric cyanohydrin synthesis
Ooi, Takashi,Miura, Tomoya,Takaya, Keisuke,Ichikawa, Hayato,Maruoka, Keiji
, p. 867 - 873 (2001)
Zr(OBut)4 can serve as an effective promoter for the Meerwein-Ponndorf-Verley alkynylation of aldehydes and also facilitate MPV type cyanide transfer to aldehyde carbonyls with commercially available acetone cyanohydrin under mild conditions. Based on this finding, a new procedure for asymmetric cyanohydrin synthesis has been developed employing (4R,5R)-2,2-dimethyl-α,α,α′,α′-tetraph enyl-1,3-dioxolane-4,5-dimethanol (TADDOL, 6) as a chiral ligand. For instance, sequential treatment of CH2Cl2 solution of 6 (1 equiv.) with Zr(OBut)4 (1 equiv.) and acetone cyanohydrin (2 equiv.) at room temperature for 1 h, and subsequent reaction with 3-phenylpropanal at -40°C for 7.5 h resulted in formation of the corresponding cyanohydrin 5g [R=Ph(CH2)2] in 63% isolated yield with 85% ee. The scope and limitations of this method have been clarified with various aldehydes as substrates.
A new (R)-hydroxynitrile lyase from Prunus mume: Asymmetric synthesis of cyanohydrins
Nanda, Samik,Kato, Yasuo,Asano, Yasuhisa
, p. 10908 - 10916 (2007/10/03)
A new hydroxynitrile lyase (HNL) was isolated from the seed of Japanese apricot (Prunus mume). The enzyme has similar properties with HNL isolated from other Prunus species and is FAD containing enzyme. It accepts a large number of unnatural substrates (benzaldehyde and its variant) for the addition of HCN to produce the corresponding cyanohydrins in excellent optical and chemical yields. A new HPLC based enantioselective assay technique was developed for the enzyme, which promotes the addition of KCN to benzaldehyde in a buffered solution (pH=4.5).
(R)-Oxynitrilase-catalyzed hydrocyanation: The first synthesis of optically active fluorinated mandelonitriles
Han, Shiqing,Chen, Peiran,Lin, Guoqiang,Huang, Hao,Li, Zuyi
, p. 843 - 846 (2007/10/03)
The first enantioselective synthesis of (R)-fluorinated mandelonitriles, by hydrocyanation under micro-aqueous conditions with almond meal as catalyst is reported.
Lipase-catalyzed transesterification of 2-hydroxy-2- (pentafluorophenyl)acetonitrile leading to (1R,2R)-and (1S,2S)-bis (pentafluorophenyl)ethane-1,2-diol
Sakai, Takashi,Miki, Yasushi,Tsuboi, Masashi,Takeuchi, Hiroaki,Ema, Tadashi,Uneyama, Kenji,Utaka, Masanori
, p. 2740 - 2747 (2007/10/03)
Optically pure (IR,2R)- and (1S,2S)-1,2-bis(pentafluorophenyl)ethane- 1,2-diol (1) were synthesized from key intermediates (R)- and (S)-2-hydroxy- 2-(pentafluorophenyl)acetonitrile (2), both of which were prepared by the lipase LIP-catalyzed transesterification (E - 465). The absolute configuration of (S)-2 was determined by X-ray structural analysis after transformation into (S)-a-cyano-2,3,4,5,6-pentafluorobenzyl (S)-6-methoxy-a- methyl-2-naphthaleneacetate (S,S)-9. In addition, the crystal structure of (S,S)-9 has an interesting well-ordered packing pattern which shows face-to- face stacking interactions and end-to-end parallel contacts between the pentafluorophenyl and 6-methoxynaphthyl groups of the adjacent molecules.
Zr(OBut)4 as a new promoter for the meerwein-ponndorf-verley alkynylation and cyanation of aldehydes
Ooi, Takashi,Takaya, Keisuke,Miura, Tomoya,Maruoka, Keiji
, p. 69 - 70 (2007/10/03)
Zr(OBut)4 can serve as an effective promoter for the Meerwein-Ponndorf-Verley alkynylation of aldehydes and it was found to be particularly attractive in the Meerwein-Ponndorf-Verley cyanation. Thieme Stuttgart.
Enzymatic Synthesis of (R)-Cyanohydrins by Three (R)-Oxynitrilase Sources in Micro-aqueous Organic Medium
Lin, Guoqiang,Han, Shiqing,Li, Zuyi
, p. 3531 - 3540 (2007/10/03)
The enantioselective synthesis of optically active (R)-cyanohydrins generated from several aromatic, heteroaromatic and aliphatic aldehydes and methyl ketones was carried out using almond, peach or loquat meal as (R)-oxynitrilase sources in diisopropylether under micro-aqueous conditions The micro-aqueous reaction system, which is superior to the conventionally used water-organic biphase reaction system, performed well over the temperature range of 4 deg C to 30 deg C.
