Benzyl hydroxyl amine

Reactions of furanose and pyranose with -benzyl hydroxyl amine at 110°C... 

Umsetzung von 1-Brom-alkanen mit N-Benzyl-hydroxylamin in Phosphorsaure-tris-[di-methylamid] (HMPT), Dehydratisierung des so gebildeten N-Alkyl-N-benzyl-hydroxyl-amins mit 2-Fluor-l-methyl-pyridinium-(4-methyl-benzolsulfonat) und saure Hydrolyse des entstandenen N-Benzyliden-amins ergibt 1-Amino-alkane in guten Ausbeuten3. 

Benzyl Hydroxyl Amine.—One of the hydroxyl amines of the benzene homologues is of importance in illustrating a case of isomerism. The compound is the hydroxyl amine derivative of toluene with the hydroxyl amine group substituted in the side chain, i.e., it is benzyl hydroxyl amine. The isomerism is due to the different hydrogen atoms of the hydroxyl amine which the benzyl group replaces. The two compounds are ... 

In the alpha compound the benzyl group replaces the hydroxyl hydrogen of hydroxyl amine while in the beta compound it replaces one of the amino hydrogens. There are also known two isomeric di-benzyl hydroxyl amines and one tri-benzyl hydroxyl amine. 

Condensation of normeperidine (81) with 3-chloropropan-l-ol affords the compound possessing the alcohol side chain (88). The hydroxyl is then converted to chlorine by means of thionyl chloride (89) displacement of the halogen by aniline yields pimino-dine (90). ° Condensation of the secondary amine, 81, with styrene oxide affords the alcohol, 91 removal of the benzyllic hydroxyl group by hydrogenolysis leads to pheneridlne (92). ... 

Two equivalents of the tertiary amine base are required, and a significant improvement in the diastereoselectivity was observed with TMEDA over DIPEA. Purification and further enrichment of the desired RRR isomer to >98% ee was achieved by crystallization. Oxidative removal of the chiral auxiliary followed by carbodiimide mediated amide formation provides (3-keto carboxamide 14 in good yield. Activation of the benzylic hydroxyl via PPha/DEAD, acylation, or phosphorylation, effects 2-azetidinone ring-closure with inversion of stereochemistry at the C4 position. Unfortunately, final purification could not be effected by crystallization and the side products and or residual reagents could only be removed by careful chromatography on silica. 

Relatively little basic information has been published regarding the kinetics of phenol-formaldehyde intermediates, especially of phenols, methylol phenols, benzyl alcohol and benzylic ethers with isocyanates. Due to the fact that a typical resole contains both phenolic and benzylic hydroxyl groups, it was of interest to determine their reactivity toward isocyanates in the presence of various catalysts, as well as the effect of substitution on their reactivity. This investigation describes the kinetics of model phenols and model benzyl alcohols with phenyl isocyanate catalyzed with either a tertiary amine (dimethylcyclo-hexylamine, DMCHA) or an organotin catalyst, dibutyltin dilaurate (DBTDL) in either dioxane or dimethylformamide solution. 

Recently, Leuck et al. [282] have described an acyl-type anchor for the fast and efficient preparation of 3 -aminoalkyl oligonucleotides based on the 2-hydroxy-methyl-6-nitrobenzoyl group (Figure 19.12). The linker is prepared from 6-nitroph-thalide by acylation of the respective aminoalcohol and attachment to LCAA-CPG through the benzylic hydroxyl via the succinyl group. Cleavage is achieved under conditions of basic hydrolysis by the intramolecular attack of the liberated hydroxyl onto the amide carbonyl with the expulsion of the amine. Complete detachment of the oligomer requires 2 h at 55 °C in concentrated ammonia or 30 min at 65 °C in 40% aqueous methylamine-concentrated aqueous ammonia (l lv/v), or can be accomplished at room temperature within 24 h in concentrated ammonia. The new anchor was shown to be superior to the phthalimido support [279] in terms of product yield and deprotection time. 

If two different methylene groups compete for creation of the pyrrole ring (as it takes place in, e.g benzyl ethyl ketoxime), the competition is won by group that is in Zt-position relative to hydroxyl, that is, by methylene function of the benzyl radical. In this case, conjugation with the benzene ring (formation of the styrene fragment) contributes additionally to stabilization of the ethylene counterpart of hydroxyl-amine O-vinyl ether formed. 

In order to explore the generality of this new domino reaction the conversion of various primary amines with 2-341 and the cyclohexane analogue was investigated (Scheme 2.81). For example, the reaction proceeds with high yields when benzyl- or (2-phenylethyl)amine are used (entries 1 and 2). In comparison, sterically more hindered amines such as 2-butylamine produced much lower yield (entry 4) Furthermore, the reaction tolerates other functional groups, such as an unprotected hydroxyl group (entry 5), and variation of the enone ring size is possible (entries 6 and 7). More recent results have revealed that the addition of Sn(OTf)2 or In(OTf)2 makes the transformation more reliable. 

Aryl alcohol oxidase from the ligninolytic fungus Pleurotus eryngii had a strong preference for benzylic and allylic alcohols, showing activity on phenyl-substituted benzyl, cinnamyl, naphthyl and 2,4-hexadien-l-ol [103,104]. Another aryl alcohol oxidase, vanillyl alcohol oxidase (VAO) from the ascomycete Penicillium simplicissimum catalyzed the oxidation of vanillyl alcohol and the demethylation of 4-(methoxymethyl)phenol to vanillin and 4-hydro-xybenzaldehyde. In addition, VAO also catalyzed deamination of vanillyl amine to vanillin, and hydroxylation and dehydrogenation of 4-alkylphenols. For the oxidation of 4-alkylphenol, the ratio between the alcohol and alkene product depended on the length and bulkiness of the alkyl side-chain [105,106]. 4-Ethylphenol and 4-propylphenol, were mainly converted to (R)-l-(4 -hydroxyphenyl) alcohols, whereas medium-chain 4-alkylphenols such as 4-butylphenol were converted to l-(4 -hydroxyphenyl)alkenes. 

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