148409-93-2Relevant academic research and scientific papers
Rh-Catalyzed Enantioselective Allylation of N-Tosyl- and N-Nosylaldimines: Total Synthesis of (-)-Crispine A
Chiang, Pei-Fen,Li, Wei-Sian,Jian, Jia-Hong,Kuo, Ting-Shen,Wu, Ping-Yu,Wu, Hsyueh-Liang
supporting information, p. 158 - 161 (2018/01/17)
The unprecedented development of asymmetric Rh-catalyzed 1,2-allylation of N-Ts- and N-Ns-aldimines is achieved. This protocol utilizes potassium allyltrifluoroborates and various aldimines to generate enantioenriched homoallylic amines in the presence of 3.0 mol % of Rh(I)/L1b catalyst with up to 90% yield, 98% ee (R = H), and 10:1 diastereoselectivity (R = Me or Ph), yielding the same major diastereomer when using potassium (E)- and (Z)-crotyltrifluoroborate. Its synthetic utility is also illustrated in the total synthesis of (-)-crispine A.
Palladium-catalyzed asymmetric umpolung allylation of imines with allylic alcohols
Qiao, Xiang-Chen,Zhu, Shou-Fei,Chen, Wang-Qiao,Zhou, Qi-Lin
experimental part, p. 1216 - 1220 (2010/10/20)
A palladium-catalyzed asymmetric umpolung allylation reaction of imines with allylic alcohols has been developed. In the presence of chiral spiro phosphoramidite ligand 4, the allylation was accomplished with high yields and good enantioselectivities. The use of highly stable and easily available allylic alcohols instead of allylic metal reagents facilitated the preparation of chiral homoallylic amines.
Reversal of diastereofacial selectivity in the nucleophilic addition reaction to chiral N-sulfinimine and application to the synthesis of indrizidine 223AB
Koriyama, Yuji,Nozawa, Akihiro,Hayakawa, Ryuuichirou,Shimizu, Makoto
, p. 9621 - 9628 (2007/10/03)
Diastereoselective addition reaction of ester enolates and Grignard reagents to optically active N-sulfinimines was examined. Reversal of the diastereofacial selectivity was realized by using appropriate metal species, solvents and additives, and the β-amino esters (up to >98% de) and the homoallylic amines (up to >98% de) were obtained in good yields. β-Amino esters thus obtained were converted to the useful β-amino acids involving (R)-homoserine. Application to the synthesis of indrizidine alkaloids was also described.
Synthesis of (S)- and (R)-1-(2-furyl)alkylamines and (S)- and (R)-α- amino acids through the addition of organometallic reagents to imines derived from (S)-Valinol
Alvaro, Giuseppe,Martelli, Gianluca,Savoia, Diego,Zoffoli, Andrea
, p. 1773 - 1777 (2007/10/03)
(S)-1-(2-Furyl)alkylamines were prepared through the addition of organometallic reagents to the imine derived from 2-furaldehyde and (S)- valinol, previous protection of the auxiliary hydroxy group as trimethylsilyl ether, followed by removal of the auxiliary. Then, protection of the primary amine as tosylamide or benzamide and oxidation of the furan ring gave the N- derivatives of (S)-α-amino acids. (R)-N-Benzoylphenylglycine was prepared from the benzaldimine, where the hydroxy group was protected as the tert- butyldimethylsilyl ether, through addition of 2-furyllithium.
An efficient preparation of optically active α-furfuryl amide by kinetic resolution using the modified Sharpless asymmetric epoxidation reagents
Zhou,Lu,Wang
, p. 2641 - 2654 (2007/10/02)
Kinetic resolution of α-furfuryl amide was first carried out by using the modified Sharpless asymmetric epoxidation reagent to give the slow-reacting enantiomers, (S)-1(a-h) and (R)-1(b,f) in high enantioselectivity (90-100% e.e) and high chemical yield (
