Diastereoselective Alkylation of 2,3,4,6-Di-O-isopropylidene-2-keto-l-gulonic Amides. Application to the Asymmetric Synthesis of 1-Substituted-1,2,3,4-tetrahydroisoquinolines and 1-Substituted-1,2,3,4,-tetrahydro-β-carbolines
摘要:
The diastereoselective alkylation of amides 3a,b and 7a,b derived from gulonic acid is described. Substituted compounds are obtained in good yield and high diastereoselectivity. A mechanistic investigation establishes that the diastereoselectivity did not arise from an initial asymmetric deprotonation. The stereochemistry is then determined during the alkylation step.
Diastereoselective Alkylation of 2,3,4,6-Di-O-isopropylidene-2-keto-l-gulonic Amides. Application to the Asymmetric Synthesis of 1-Substituted-1,2,3,4-tetrahydroisoquinolines and 1-Substituted-1,2,3,4,-tetrahydro-β-carbolines
摘要:
The diastereoselective alkylation of amides 3a,b and 7a,b derived from gulonic acid is described. Substituted compounds are obtained in good yield and high diastereoselectivity. A mechanistic investigation establishes that the diastereoselectivity did not arise from an initial asymmetric deprotonation. The stereochemistry is then determined during the alkylation step.
Diastereoselective Alkylation of 2,3,4,6-Di-<i>O</i>-isopropylidene-2-keto-<scp>l</scp>-gulonic Amides. Application to the Asymmetric Synthesis of 1-Substituted-1,2,3,4-tetrahydroisoquinolines and 1-Substituted-1,2,3,4,-tetrahydro-β-carbolines
The diastereoselective alkylation of amides 3a,b and 7a,b derived from gulonic acid is described. Substituted compounds are obtained in good yield and high diastereoselectivity. A mechanistic investigation establishes that the diastereoselectivity did not arise from an initial asymmetric deprotonation. The stereochemistry is then determined during the alkylation step.