Cyanamides, addition hydrolysis

A second method is due to J. von Braun and consists in the addition of cyanogen bromide to tertiary cyclic bases.1 In the unstable addition product a C—N-linkage is broken and at the same time the bromine wanders to a new position. A brominated derivative of cyanamide is produced and this, on hydrolysis, yields a secondary amine which can be broken down further, e.g. 

Hydrolysis of cyanamides 6-13 Addition of ammonia to aldehydes 6-15 Reductive alkylation of ammonia or amines... 

Cyanamides, alcoholysis, 648 hydrolysis, 647, 680 Cyanides, acylation, 348 addition, of alcohols to, 634 of ammonia or amines to, 635 of olefins to, 571 alcoholysis, 485, 542 alkylation, 599 amination, 636 carbethoxylation, 489 condensation to /3-iminonitriles, 730 hydrolysis, to acids, 412 to amides, 570 preparation, 590... 

Diamines.- The preparation of vicinal diamines by functionalisation of olefins remains an area of active research interest. Full details concerning a previously reported synthesis of vic-primary diamines via -bromosuccinimide-mediated addition of cyanamide to unactivated double bonds followed by formation and subsequent hydrolysis of a 2-ethoxyimidazoline have been published. 

In addition to the physiological reaction, the reversible hydration of CO2 to bicarbonate (reaction 1, Scheme 1), CAs catalyze a variety of other reactions, such as the hydration of cyanate to carbamic acid, or of cyanamide to urea (reactions 2 and 3) the aldehyde hydration to gem-diols (reaction 4) the hydrolysis of carboxylic, or sulfonic (reactions 5, 6), as well as other less investigated hydrolytic processes, such as those described by equations 7-10 in Scheme 1 (Supuran et al., 1997 Supuran and Scozzafava, 2000b Guerri et al., 2000). It should be mentioned that the previously reported phosphatase activity of CA III was recently proved to be an artefact (EGm et al., 2000). It is unclear at this moment whether CA catalyzed reactions other than the CO2 hydration has physiological significance. 

Despite the fact that boehmite is a naturally occurring mineral, the majority of commercial samples are man-made, often by the hydrolysis/thermolysis of aluminum salts. In addition, they commonly contain significant quantities of gibbsite, A1(0H)3, and are of variable porosity. Although we have shown die reactions discussed below to be applicable for samples from different commercial sources, to be self consistent we have chosen to discuss results obtained using a single source of low gibbsite (> 99 % boehmite) obtained from American Cyanamid. 

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