Hydrido cuprates

Prim, und sek. Sulfonsaure-ester lassen sich selektiv auch mit den Systemen 2 Lithium-trimethoxy-hydrido-aIuminat/Kupfer(I)-jodid6 und Lithium-butyl-hydrido-cuprat(I)7 zu... 

Semmelhack et al. chose CuBr, together with either Red-Al or LiAl(OMe)3H in a 1 2 ratio, to afford presumed hydrido cuprates, albeit of unknown composition [llj. In THF, both the former Na complex and the latter Li complex are heterogeneous (and of differing reactivities), yet each is capable of 1,4-reductions of unsaturated ketones and methyl esters (Eq. 5.4). Commins has used a modified version, prepared from lithium tri-t-butoxy-aluminium hydride and CuBr (in a 3 4.4 ratio), to reduce a 3-substituted-N-acylated pyridine regioselectively at the a-site [12]. 

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