Notizen. Die Metallierung von <i>N,N,N′,N′</i>‐Tetramethylethylendiamin (TMEDA)

Abstract

The Metalation of N,N,N′,N′ ,‐Tetramethylethylenediamine (TMEDA) TMEDA may be metalated with good regioselectivity: tert ‐BuLi attacks preferably a methyl group whereas a methylene group is deprotonated by n ‐BuLi/ tert ‐BuOK. Thus, trapping with Me 3 SnCl and hydrolytic work‐up give either 53% of Me 2 N[CH 2 ] 2 NMe(CH 2 SnMe 3 ) ( 2 ) and 5% of (Me 3 Sn)(Me 2 N)CCH 2 ( 3 ) or 3 alone (42%), respectively. 3 is formed from deprotonated TMEDA by elimination of amide which can be trapped as Me 2 N(SnMe 3 ) ( 5 ); some trans ‐(Me 3 Sn)CHCH(NMe 2 ) ( 4 ) is also obtained. The structures of the compounds follow mainly from 1 H‐, 13 C‐, 15 N‐, and 119 Sn‐NMR data.