Selective Synthesis of 1-Dialkylamino-2-alkylbicyclo-[1.1.1]pentanes
Xiaoshen Ma1, Yongxin Han1, David J Bennett1
1Department of Discovery Chemistry, Merck & Co., Inc., 33 Avenue Louis Pasteur, Boston, Massachusetts 02115, United States.
Abstract:
Compared to the abundance of methodologies accessing 1-substituted and 1,3-disubstuted bicyclo[1.1.1] pentanes (BCPs), the synthetic accessibility of BCPs with substitutions at the methylene position has been limited. Herein, we report a selective synthesis of 1-dialkylamino-2-alkylbicyclo[1.1.1]pentanes from prefunctionalized starting materials. We also achieved further functionalizations of these 1,2-disubstituted BCPs and developed a synthesis of these compounds with minimum necessity of chromatographic purifications starting from 1,3-dichloroacetone. Finally, we also detailed the synthesis of a 1,2,3-trisubstituted BCP analogue.
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