Carbohydrates as Chiral Templates: Diastereoselective Synthesis of N-Glycosyl-N-homoallylamines and @-Amino Acids from Imines
نویسندگان
چکیده
Complexing properties and chirality of carbohydrates were utilized in diastereoselective reactions of 0-pivaloylated N-galactosylimines with allylsilanes and -stannaries. With dyltrimethylsilane in the presence of SnCh, imines 2 of aromatic and heteroaromatic aldehydes were converted to homdylamines 3, giving ratios of diastereomers higher than 7:l. No addition products derived from a-anomeric aromatic imines were formed. Aliphatic homdylamines 3 were synthesized by using allyltributylstannane in the presence of SnCh. Both aand Banomeric aliphatic imines reacted with the allylstannane. They gave the same ratio of diastereomers and showed the same sense of asymmetric induction.
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