Cyclohexanediol 3-amino

The type 2 reaction is in fact the same reaction that is favoured by the cyclization possibility if there is a heteroatom in a convenient position. The latter probably also provides anchimeric assistance to the expulsion of a neutral fragment. The example of cyclohexanediols provides a good illustration. As is shown by the following data, the comparison of ty-amino alcohols H2N(CH2) OH with various linear chain lengths also... 

Photooxidation rates of propan-2-ol in aqueous Ti02 suspensions are reported to be increased by ultrasound radiation, an observation which has been rationalised in terms of mass transport of the substrate and activation of the solid catalyst. The value of the newly described photochemical rearrangement of 2-phenylthio-l,3-cyclohexanediols such as (69) to deoxysugars (70) which are in equilibrium with the closed form (71) has been illustrated by its application to the synthesis of (+)-m-rose oxide (72), and the same authors have also described the regioselective photorearrangement of 2-phenylthio-3-aminocyclohexanols (73) to deoxyazasugars (74) this has proved to be useful in the synthesis of various piperidines (75), amino-sulfones, -sulfoxides and -acids. Hydroxy(alkoxy)methyl radicals have been generated by photo-induced electron transfer. ... 

There are few reports of successful one-step synthesis of primary diamines, and the examples are limited to amines with a special structure. Amination of 1,4-cy-clohexanediol in supercritical ammonia (135 bar) over a Co-Fe catalyst alforded 67 % 1,4-diaminocyclohexane [21]. Excess ammonia, as both supercritical solvent and reactant, and short contact time in the continuous fixed-bed reactor favored the desired reactions. In the best example the cumulative selectivity for the diamine and the intermediate amino alcohol was 97 % at 76 % conversion. Recycling of the unreacted diol and amino alcohol can provide an alternative to the eurrent process, the hydrogenation of pnra-phenylenediamine. The high seleetivity was because of the rigid structure and the relative positions of OH functionality in the substrate. For comparison, amination of 1,4-butanediol under similar conditions yielded pyiTolidine as the major product 1,4-diaminobutane was barely detectable. When 1,3-cyclohexanediol was aminated with the same catalyst in the continuous system, the yield of 1,3-diaminoeyclohexane dropped below 5%, mainly because elimination of water led to undesired monofunctional products via a,/9-unsaturated alcohol, ketone, and/or amine intermediates [22]. 

As shown in Table 9.16, assembly of alkenylsulfides could be achieved through couphng of vinyl halides with thiols. The suitable catalytic systems are [Cu(phen) (PPh3)2]N03 (L13) (Table 9.16, entry 1) [78], CuX/amino acid (LI and L2) (entries 2 and 3) [79, 80], and Cul/ds-l,2-cyclohexanediol (L21) that was found recently to be a quite efficient system (entry 4) [81], Among them, Cul/L21 led the reaction to occur at 30-60 °C, providing corresponding vinyl sulfides in excellent yields, even from hindered and functional thiols. 

Racemic (l,3/2)-l-benzyloxycarbonylamino-3-0-ethyl- and (l,2/3)-3-benzyl-oxycarbonylamino-l-O-ethyl-cyclohexanediols (prepared from 3-ethoxycyclo-hexene) have been condensed under Koenigs-Knorr conditions with 3,4,6-tri-O-acetyl-2-deoxy-2-(2,4-dinitrophenyl)amino-a-D-glucopyranosyl bromide to yield... 

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