330455-53-3

Upstream product

• 630-19-3 pivalaldehyde 
• 91-00-9 Benzhydrylamine 

Downstream Products

• 124655-17-0 (R)-2-(tert-butoxycarbonylamino)-3,3-dimethylbutanoic acid 
• 442568-35-6 (R)-benzyl 2-(tert-butoxycarbonylamino)-3,3-dimethylbutanoate 
• 24590-76-9 N-(diphenylmethylidene)-2,2-dimethylpropylamine 

Relevant academic research and scientific papers

Efficient transamination under mild conditions: Preparation of primary amine derivatives from carbonyl compounds via imine isomerization with catalytic amounts of potassium tert-butoxide

1,3-Prototropic rearrangement of N-diphenylmethanimines was successfully performed with a catalytic amount of potassium tert-butoxide. This procedure can also be used with aliphatic and aromatic aldimines and was extended to the isomerization of (1R)-camphorquinone monoimine and N-(4-methoxyphenyl)-4-phenyl-3-iminoazetidin-2-one. The isomerized imines were easily hydrolyzed and isolated as Cbz derivatives.

COMPOUNDS AND RELATED METHODS OF USE

Described herein are compounds of formula (I), related compositions, and their use, for example in the formation of α-amino acids or a precursor thereof such as an α-aminonitrile.

Activation of the Si-B Linkage: Copper-Catalyzed addition of nucleophilic silicon to imines

Activation of the Si-B bond through copper-catalyzed transmetalation quickly developed into a practical method to generate Cu-Si reagents These silicon nucleophiles cleanly add to aldehyde-derived imine electrophiles to form R-silylated amines in protic media, and no carbon-tonitrogen Brook-type rearrangement of the intermediate anion is observed. Aside from electron-withdrawing groups at the imine nitrogen atom, for example, SO2Tol and P(O)Ph2, previously delicate nitrogen substituents such as phenyl or benzhydryl are tolerated. The same protocol also allows the unprecedented addition to representative ketone-derived imines.

Asymmetric Strecker reaction of N-benzhydrylimines utilising new tropos biphenyldiol-based ligands

The synthesis of a library of N-arenesulfonyl-1,3-oxazolidinyl-substituted biphenyldiols is presented. A set of two central intermediates together with easily accessible N-arenesulfonylamino alcohols furnish a broad variety of 1,3-oxazolidines. These are applied as chiral tropos ligands in a titanium-mediated Strecker-type reaction of N-benzhydrylimines. A correlation between the ee values in the product and the diastereomeric ratio concerning the chiral axis of the ligand is made. Those substituents in the ligand which proved to lead to a higher preference for one diastereomeric conformer of the chiral axis in related compounds now provide the most selective ligands. Two privileged ligands are identified that afford superior results in 8 of 13 screenings. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.

Regulation of orthogonal functions in a dual catalyst system. Subservient role of a nonchiral lewis acid in an asymmetric catalytic heteroatom Diels-Alder reaction

A catalytic asymmetric heteroatom Diels-Alder reaction of unactivated imines with Danishefsky's diene is described which gives high asymmetric induction for N-benzhydryl imines derived from a variety of aldehydes. The catalyst is derived from B(OPh)3 and the VAPOL ligand and gives good induction, but the reaction stalls and does not give high conversion (～50%). It was found that in the presence of both the chiral catalyst and excess amounts of B(OPh)3 the reaction proceeds to completion and gives high yields of the dihydropiperidinone product. Despite the presence of large quantities of the nonchiral Lewis acid B(OPh)3, the asymmetric induction of the product remains constant (90% ee) as the amount of B(OPh)3 is steadily increased and does not drop off until the ratio of B(OPh)3 to VAPOL is 100:1 (82% ee). These observations are interpreted as involving highly separated and different activities for the chiral and nonchiral Lewis acids present in the reaction. Specifically, the excess B(OPh)3 serves to bind to the product and release the chiral catalyst to turnover more starting material. The B(OPh)3 does not compete in turning over the starting material, and a series of binding studies reveal that this is likely due to a combination of two factors. The binding studies reveal that the chiral catalyst binds to the starting imine 7 times more strongly than does B(OPh)3. However, in order to explain the constant asymmetric induction observed despite the addition of increasing amounts of B(OPh)3, the rate of the reaction of the imine complexed with the chiral catalyst must be at least 10 times faster than the reaction of the imine complexed with B(OPh)3. Finally, a catalyst generated from BINOL and B(OPh)3 does not show this phenomenon. Copyright