Asymmetric syntheses of optically active .alpha.,.beta.-disubstituted .beta.-amino acids

Hydroboration, Diboration, Silylboration, and Stannylboration

“…The effect of the TsNH group is strongly enhanced by N-benzylation to give the TsNBn group, since the bulkiness of the allylic substituent serves to increase the syn-diastereoselectivity (70) [84], as is discussed in Scheme 1-17. Although 9-BBN unexpectedly results in the same diastereoselection to that of the catalyzed reaction, the borane-tetrahydrofurane complex selectively yields anti-amino alcohols (71) [85], which are a versatile intermediate for the synthesis of optically active β-amino acids via the RuCl 3 -catalyzed oxidation of alcohols with NaIO 4 .…”

Molecular‐Weight‐Enlarged Multiple‐Pincer Ligands: Synthesis and Application in Palladium‐Catalyzed Allylic Substitution Reactions

“…These reactions find applications in total synthesis reactions [40] as well as in the synthesis of amino acids, alkaloids, or carbohydrate derivatives by transformation of the allyl amines produced by the allylic amination reaction. [41][42][43] These substitution reactions have also become a method for testing and comparing novel mono-and bidentate phosphorus ligands, either chiral or achiral. The experimental conditions are very mild: the reaction is carried out at room temperature and at ambient pressure in common organic solvents such as dichloromethane and THF or in more polar solvents such as methanol, N,N-dimethylform-A C H T U N G T R E N N U N G amide (DMF), and dimethyl sulfoxide (DMSO).…”

Procedures for and Possible Mechanisms of Pd‐Catalyzed Allylations of Primary and Secondary Amines with Allylic Alcohols

“…Furthermore, allylamines are valuable synthetic intermediates [10] for the preparation of numerous compounds, such as amino acids, [11] piperidines, [12] and azacarbohydrates, [13] and also for reactions involving ringclosing alkene metathesis methodology. [14] Since the acceptance of our reviews, [15] the synthesis of allylic amines from allylic alcohols via η 3 -allylpalladium intermediates has been the subject of new reports and it seems of interest to highlight this topic in commenting on the reaction mechanisms.…”