Copper amides

Copper nitrate reacts with sodamide and ammonia by forming explosive copper amides. The oxidising properties of this nitrate have led to violent detonations with ammonium hexacyanoferrates heated to 220 C in the presence of water traces, or dry at the same temperature, but in the presence of an excess of hexacyanoferrate. These accidents illustrate once more the incompatibility between compounds with a cyano group (or cyanide anion) and oxidants. An accident also occurred with a potassium hexacyanoferrate. 

This procedure is apparently limited to cyanomethylcopper derivatives, copper amides, heteroarylcopper compounds, and copper thiolates. Use of bis(iodomethyl)-zinc, (ICH2)2Zn, results in products from double insertion. 

All these reactions proceed by initial base-promoted formation of copper amide complexes 306A from diarylamines or sulfonamides 306 or 308, respectively, which are subject to a concerted, sv -amidocupration with the adjacent alkene unit via transition state 306B (Fig. 82). The resulting alkylcopper(II) intermediates 306C are... 

The first epoch-making catalytic process was developed by using a chiral copper amide derived from an amine 16 in 1990. With 3 mol% of aminotroponeimine (16) and copper, butylmagnesium chloride reacted with cyclohexenone to afford the corre.sponding adduct in 74% ee (Eq. (12.20)) [45]. 

Silver and copper amides as the simplest acid/base catalysts for stereoselective carbon—carbon bond-forming reactions, particularly [3+2] cycloaddition reactions 13CEJ9420. 

When the reaction is carried out with (BuOCu, in the absence of a lithium salt, yields and enantioselectivities are not affected. This indicates that the diamine coordinates to the copper atom at the enantio-differentiating step, even in the presence of the cationic lithium atom. In addition, ESl-MS experiments support the presence of complex O (Scheme 70). Shibasaki et al. have proposed a working hypothesis for the catalytic cycle, as shown in Scheme 70. Copper amide P is generated from O and (BuOLi, and next, the copper-nitrogen bond cleaves... 

Tertiary Amines.—A new approach to the direct alkylation of secondary amines leading to tertiary amines is based on the oxidative coupling of lithium alkyl copper amides (Scheme 16). The method is also applicable to the synthesis of secondary amines. 

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