Amino alcohols peroxidation production

The stereochemical course of reduction of imonium salts by Grignard reagents was found to depend on the structure of the reagent 714). Hydro-boration of enamines and oxidation with hydrogen peroxide led to amino-alcohols (7/5). While aluminum hydrogen dichloride reacted with enamines to yield mostly saturated amines and some olefins on hydrolysis, aluminum hydride gave predominantly the unsaturated products 716). 

Asymmetric hydroboration of enamines with chiral diboranes, followed by oxidation with hydrogen peroxide, in aqueous sodium hydroxide, gives /1-amino alcohols in good yields and high ee (equation 29)153. The products of this reaction are useful in medicinal applications and as synthons for further synthetic elaboration. 

The reaction of 5-amino-l,2,4-thiadiazoles (16) with aldehydes produces a-amino alcohols (145), azomethines (146) or bis-amines (147) depending on the reactants and reaction conditions, as illustrated in Scheme 58. The nitration of 5-amino-3-methyl-l,2,4-thiadiazole (25) in a mixture of 98% sulfuric acid and 95% nitric acid at 0°C is reported to produce (148) in good yield (65AHC(5)119), but a similar reaction with 3-amino-l,2,4-thiadiazoles has not been described. Products of type (149) can be obtained, however, by the ring closure of Af-nitro-AT-thiocarbamylguanidines with alkaline hydrogen peroxide. 

Botanical extracts such as lanolin. Aloe vera, Centella asiatica or glycyrrhetic acid are studied. Vitamins such as A, C, B5 and E have also been reported. Studies on the following compounds used as ingredients can also be found heterocyclic compounds, organic acids, thiocompounds, alkanolamines, amines, amino acids, alcohols, peroxides, amides, polymers, peptides and ceramides. Analytical methods to determine toxic compounds present as impurities or as by-products such as nitrosamines, phenols, pesticides, polychlorinated biphenyls, etc. have also been proposed in literature. 

---