Highly Selective 5-Substitution of 3-Methylthiophene via Directed Lithiation
作者:Keith Smith、Mark Lewis Barratt
DOI:10.1021/jo062024f
日期:2007.2.1
Lithiation of 3-methylthiophene with lithium 2,2,6,6-tetra-methylpiperidide (LiTMP) is highly selective at the 5-position, and reaction with a range of electrophiles gives high yields of the corresponding 2,4-disubstituted thiophenes, even when unhindered electrophiles are used.
A metal-free and a solvent-free synthesis of thio-amides and amides: an efficient Friedel–Crafts arylation of isothiocyanates and isocyanates
A rapid, metal-free and solvent-free (very low loading of solvent in few cases) reaction conditions for synthesizing thioamides and amides using a Bronsted super acid such as triflic acid has been developed.