HSAB Driven chemoselectivity in alkylation of uracil derivatives. A high yielding preparation of 3-alkylated and unsymmetrically 1,3-dialkylated uracils

doi:10.1016/S0040-4020(99)00736-X

Tetrahedron

Volume 55, Issue 43, 22 October 1999, Pages 12615-12628

https://doi.org/10.1016/S0040-4020(99)00736-X Get rights and content

Abstract

A qualitative hardness scale (N¹<N³<O⁴) has been found for the conjugated bases of 2-methoxy-4(3H)-pyrimidinones 1–3 and applied to high yielding chemoselective N³ methylation, ethylation and benzylation reactions. Removal of the 2-methoxy group followed by a second alkylation affords unsymmetrically 1,3-disubstituted uracils.

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HSAB Driven chemoselectivity in alkylation of uracil derivatives. A high yielding preparation of 3-alkylated and unsymmetrically 1,3-dialkylated uracils

Abstract

Tetrahedron

Tetrahedron Lett.

Tetrahedron Lett.

Chem. Ber.

Chem. Ber.

Chem. Ber.

Chem. Ber.

J. Chem. Educ.

J. Chem. Soc.

J. Chem. Soc.

J. Med. Chem.

Collect. Czech. Chem. Commun.

J. Org. Chem.

J. Org. Chem.

Biopolymers

Chem. Lett.

J. Chem. Soc. Perkin Trans. 1

Acta Chem. Scand.

J. Chem. Soc. Perkin Trans. 1

Synthesis

J. Org. Chem.

Nucleic Acid Research

Izvestiya Akademii Nauk SSSR Seriya Khimickesaya

J. Am. Chem. Soc.

Chem. Pharm. Bull.

Chem. Pharm. Bull.

Adv. Heterocycl. Chem.

J. Org. Chem.