688362-39-2Relevant academic research and scientific papers
Transition metal-free trifluoromethylation of n-Allylamides with sodium Trifluoromethanesulfinate: Synthesis of Trifluoromethyl-containing oxazolines
Yu, Jipan,Yang, Haijun,Fu, Hua
, p. 3669 - 3675 (2014)
A transition metal-free method for the trifluoromethylation of N-allylamides has been developed, and the corresponding trifluoromethylcontaining oxazolines were prepared in moderate to good yields. The protocol uses readily available substituted N-allylamides as the starting materials, inexpensive and easily stored sodium trifluoro- ACHTUNGTRENUNGmethanesulfinate as the trifluoromethyl source, iodobenzene diacetate as the oxidant, and the procedure involves sequential intermolecular trifluoromethylation of alkenes with sodium trifluoro- ACHTUNGTRENUNGmethanesulfinate and intramolecular cyclization. This is the first example to prepare CF3-containing oxazolines. Therefore, the present method should afford an efficient and practical strategy for synthesis of other CF3-containing cyclic compounds.
Rhodium-Catalyzed Regiodivergent Hydrothiolation of Allyl Amines and Imines
Kennemur, Jennifer L.,Kortman, Gregory D.,Hull, Kami L.
supporting information, p. 11914 - 11919 (2016/10/06)
The regiodivergent Rh-catalyzed hydrothiolation of allyl amines and imines is presented. Bidentate phosphine ligands with larger natural bite angles (βn ≥ 99°), for example, DPEphos, dpph, or L1, promote a Markovnikov-selective hydrothiolation in up to 88% yield and >20:1 regioselectivity. Conversely, when smaller bite angle ligands (βn ≤ 86°), for example, dppbz or dppp, are employed, the anti-Markovnikov product is formed in up to 74% yield and >20:1 regioselectivity. Initial mechanistic investigations are performed and are consistent with an oxidative addition/olefin insertion/reductive elimination mechanism for each regioisomeric pathway. We hypothesize that the change in regioselectivity is an effect of diverging coordination spheres to favor either Rh-S or Rh-H insertion to form the branched or linear isomer, respectively.
Kinetic resolution of primary allylic amines via palladium-catalyzed asymmetric allylic alkylation of malononitriles
Wang, Yong,Xu, Ya-Nan,Fang, Guo-Sheng,Kang, Hong-Jian,Gu, Yonghong,Tian, Shi-Kai
supporting information, p. 5367 - 5371 (2015/05/20)
A range of primary allylic amines were resolved with selectivity factors of up to 491 through [Pd(allyl)Cl]2/(S)-BINAP-catalyzed and mesitylsulfonyl hydrazide-accelerated asymmetric allylic alkylation of malononitriles involving enantioselectiv
Asymmetric synthesis of α- And β-amino acids by diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl) imines
Almansa, Raquel,Collados, Juan F.,Guijarro, David,Yus, Miguel
experimental part, p. 1421 - 1431 (2010/11/02)
The diastereoselective addition of triorganozincates to (R)-N-(tert-butanesulfinyl)imines has been used as a key step to achieve the synthesis of highly enantiomerically enriched N-protected α- and β-amino acids. Desulfinylation of the addition products followed by benzoylation of the nitrogen atom of the obtained primary amines and oxidation of one of the substituents on the carbon atom connected to the nitrogen complete the sequence. Using the same configuration in the sulfinyl chiral auxiliary, α-amino acids with the (R) or the (S) configuration can be prepared by choosing the proper combination of imine and organozincate. α,α- Disubstituted α-amino esters with high enantiomeric purity can also be prepared when α-imino esters are the starting substrates.
Application of the addition of triorganozincates to N-(tert-butanesulfinyl)imines to the enantioselective synthesis of α-amino acids
Almansa, Raquel,Guijarro, David,Yus, Miguel
scheme or table, p. 4188 - 4190 (2009/12/01)
Highly enantiomerically enriched N-protected α-amino acids can be easily prepared from optically pure N-(tert-butanesulfinyl)imines by a four-step sequence involving: diastereoselective addition of a triorganozincate to the imine, removal of the sulfinyl group, benzoylation of the nitrogen atom of the obtained primary amine and oxidation of one of the substituents on the carbon atom α to the nitrogen. Using the same configuration in the sulfinyl chiral auxiliary, amino acids with the (R) or the (S) configuration can be prepared by choosing the proper combination of imine and organozincate. α,α-Disubstituted α-amino esters with high optical purity can also be prepared by the diastereoselective addition of trialkylzincates to α-imino esters.
Synthesis of highly enantiomerically enriched amines by the diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl)imines
Almansa, Raquel,Guijarro, David,Yus, Miguel
experimental part, p. 2484 - 2491 (2009/04/11)
The reaction of triorganozincates with (R)-N-(tert-butanesulfinyl) imines gives the expected α-branched sulfinamides in good to excellent yields with diastereomeric ratios of up to 98:2. The N-sulfinyl group of the products can be easily removed by acidic treatment, affording the corresponding chiral primary amines in enantiomeric excesses of up to 96%. The reactivity and the selectivity shown by the triorganozincates are different from the ones observed with the corresponding Grignard reagents, which allows, in several cases, the preparation of both enantiomers of an amine from the same imine substrate. When mixed triorganozincates are used, one can take advantage of the slow transfer rate of the methyl group to use it as a non-transferable one. Both aromatic and aliphatic aldimines, as well as activated ketimines, are good substrates for these addition reactions.
Enantioselective synthesis of 1-aryl-2-propenylamines: A new approach to a stereoselective synthesis of the Taxol side chain
Castagnolo, Daniele,Armaroli, Silvia,Corelli, Federico,Botta, Maurizio
, p. 941 - 949 (2007/10/03)
A variety of substituted 1-aryl-2-propenylamines of high enantiomeric purity were prepared via lipase-catalysed resolution of the corresponding racemates. (R)-1-Phenyl-2-propenylamine was further synthesised into (2R,3S)-3-benzoylamino-2-hydroxy-3-phenylpropanoic acid methyl ester, the side chain of Taxol.
