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Pyrrole-Protected ?-Aminoalkylzinc Reagents for the Enantioselective Synthesis of Amino-Derivatives.

ABSTRACT: Chiral ?-aminoalkylzinc halides were prepared starting from optically pure commercial ?-amino-alcohols. These amino-alcohols were converted to the corresponding N-pyrrolyl-protected alkyl iodides which undergo a zinc insertion in the presence of LiCl (THF, 25?°C, 10-90?min). Subsequent Negishi cross-coupling or acylation reactions with acid chlorides produced amino-derivatives with retention of chirality. Diastereoselective CBS-reductions of some prepared N-pyrrolyl-ketones provided 1,3-subsituted N-pyrrolyl-alcohols with high diastereoselectivity. Additionally, a deprotection procedure involving an ozonolysis allowed the conversion of the pyrrole-ring into a formamide without loss of optical purity.

SUBMITTER: Leroux M

PROVIDER: S-EPMC7497206 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Pyrrole-Protected β-Aminoalkylzinc Reagents for the Enantioselective Synthesis of Amino-Derivatives.

Leroux Marcel M Huang Wan-Yun WY Lemke Yannick Y Koller Thaddäus J TJ Karaghiosoff Konstantin K Knochel Paul P

Chemistry (Weinheim an der Bergstrasse, Germany) 20200629 41

Chiral β-aminoalkylzinc halides were prepared starting from optically pure commercial β-amino-alcohols. These amino-alcohols were converted to the corresponding N-pyrrolyl-protected alkyl iodides which undergo a zinc insertion in the presence of LiCl (THF, 25 °C, 10-90 min). Subsequent Negishi cross-coupling or acylation reactions with acid chlorides produced amino-derivatives with retention of chirality. Diastereoselective CBS-reductions of some prepared N-pyrrolyl-ketones provided 1,3-subsitut ...[more]

PMID: 32196786

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