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A green, economical synthesis of ?-ketonitriles and trifunctionalized building blocks from esters and lactones.

ABSTRACT: The acylation of the acetonitrile anion with lactones and esters in ethereal solvents was successfully exploited using inexpensive KOt-Bu to obtain a variety of ?-ketonitriles and trifunctionalized building blocks, including useful O-unprotected diols. It was discovered that lactones react to produce the corresponding derivatized cyclic hemiketals. Furthermore, the addition of a catalytic amount of isopropanol, or 18-crown-6, was necessary to facilitate the reaction and to reduce side-product formation under ambient conditions.

SUBMITTER: Pienaar DP

PROVIDER: S-EPMC6902896 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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A green, economical synthesis of β-ketonitriles and trifunctionalized building blocks from esters and lactones.

Pienaar Daniel P DP Butsi Kamogelo R KR Rousseau Amanda L AL Brady Dean D

Beilstein journal of organic chemistry 20191206

The acylation of the acetonitrile anion with lactones and esters in ethereal solvents was successfully exploited using inexpensive KO<i>t</i>-Bu to obtain a variety of β-ketonitriles and trifunctionalized building blocks, including useful <i>O</i>-unprotected diols. It was discovered that lactones react to produce the corresponding derivatized cyclic hemiketals. Furthermore, the addition of a catalytic amount of isopropanol, or 18-crown-6, was necessary to facilitate the reaction and to reduce s ...[more]

PMID: 31839839

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