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Catalytic discrimination between formyl groups in regio- and stereoselective intramolecular cross-aldol reactions.

ABSTRACT: Catalytic discrimination between inequivalent formyl groups was achieved using an aniline-type acid-base catalyst for the regio-, diastereo-, and enantioselective intramolecular cross-aldol reactions of enolizable dials. Although l-proline gave a mixture of the regio- and stereoisomeric products in the presence of an N-containing 1,6-dial, the aniline-type catalyst afforded anti-3,4-disubstituted pyrrolidine in high regio-, and stereoselectivity beyond the background reaction, which led to the regioisomeric 2,3-disubstituted products. The mild reactivity of the aniline-type amine facilitated catalytic discrimination between the inequivalent formyl groups. Kinetic isotope effect studies and reductive amination experiments suggested that the regioselectivity was controlled under the enamine-forming steps.

SUBMITTER: Baba T

PROVIDER: S-EPMC6013812 | biostudies-other | 2016 Jun

REPOSITORIES: biostudies-other

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Catalytic discrimination between formyl groups in regio- and stereoselective intramolecular cross-aldol reactions.

Baba Tomonori T Yamamoto Junya J Hayashi Kazuhiro K Sato Makoto M Yamanaka Masahiro M Kawabata Takeo T Furuta Takumi T

Chemical science 20160222 6

Catalytic discrimination between inequivalent formyl groups was achieved using an aniline-type acid-base catalyst for the regio-, diastereo-, and enantioselective intramolecular cross-aldol reactions of enolizable dials. Although l-proline gave a mixture of the regio- and stereoisomeric products in the presence of an <i>N</i>-containing 1,6-dial, the aniline-type catalyst afforded <i>anti</i>-3,4-disubstituted pyrrolidine in high regio-, and stereoselectivity beyond the background reaction, whic ...[more]

PMID: 30155021

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