5933-40-4Relevant articles and documents
Deactivation mechanisms of iodo-iridium catalysts in chiral amine racemization
Kwan, Maria H.T.,Pokar, Nisha P.B.,Good, Catherine,Jones, Martin F.,Munday, Rachel,Screen, Thomas,Blacker, A. John
supporting information, (2020/12/29)
The homogenous, [IrCp?I2]2, SCRAM catalyst (1) is active in the racemization of chiral amines. NMR, kinetic and structural mechanistic studies have determined the cause of catalyst deactivation to occur when ammonia or methylamine are liberated by hydrolysis or aminolysis of the intermediate imine, which tightly coordinate to the iridium centre to block turnover. Control of moisture and substrate concentration can suppress deactivation, whilst partial reactivation of spent catalyst was identified using hydroiodic acid.
Synthesis of limonene β-amino alcohol from (R)-(+)-α-methylbenzylamine and (+)-limonene 1,2-epoxide
Ait Said, Lyazid,El Bachiri, Abdelhadi,El Haimer, Chaimaa,El Hammoumi, Mohamed Merouane,Khoukhi, Mostafa
, (2021/06/02)
Two new compounds of β-amino alcohol are obtained using (R) - (+) - α-methylbenzylamine as starting material which is converted into two amines. Each of these compounds reacted in excess with a 1: 1 mixture of cis and trans-limonene oxide in the presence of water as a catalyst. The products obtained show that β-amino alcohol derived from trans-limonene oxide is obtained and unreacted cis-limonene oxide from the reaction mixture as well as the amine is attained. Whereas the addition of the synthesized carbamate of the same primary amine over the 1: 1 mixture of cis and trans -limonene oxide in the presence of water results in the hydrolysis product and the recovery of unreacted trans-limonene oxide.
Asymmetric Synthesis of Primary and Secondary β-Fluoro-arylamines using Reductive Aminases from Fungi
González-Martínez, Daniel,Cuetos, Aníbal,Sharma, Mahima,García-Ramos, Marina,Lavandera, Iván,Gotor-Fernández, Vicente,Grogan, Gideon
, p. 2421 - 2425 (2020/03/25)
The synthesis of chiral amines is of central importance to pharmaceutical chemistry, and the inclusion of fluorine atoms in drug molecules can both increase potency and slow metabolism. Optically enriched β-fluoroamines can be obtained by the kinetic resolution of racemic amines using amine transaminases (ATAs), but yields are limited to 50 %, and also secondary amines are not accessible. In order to overcome these limitations, we have applied NADPH-dependent reductive aminase enzymes (RedAms) from fungal species to the reductive amination of α-fluoroacetophenones with ammonia, methylamine and allylamine as donors, to yield β-fluoro primary or secondary amines with >90 % conversion and between 85 and 99 % ee. In addition, the effect of the progressive introduction of fluorine atoms to the α-position of the acetophenone substrate reveals the effect of mono-, di- and tri-fluorination on the proportion of amine and alcohol in product mixtures, shedding light on the promiscuous ability of imine reductase (IRED)-type dehydrogenases to reduce fluorinated acetophenones to alcohols.
