Camphor oximes

Fry and Newberg 1,2> examined the electrochemical reduction of nor-camphor oxime (109) and camphor oxime (110) to the corresponding amines. The results of this study are shown in Table 3. It is clear from a comparison of these data with those in Table 2 that the electrochemical reduction of oximes 109 and 110 takes a very different stereochemical course from reduction of the corresponding anils 103 and 104. Reduction of oximes apparently proceeds under kinetic control, affords products corresponding to protonation at carbon from the less hindered side of the carbon-nitrogen double bond, and affords the less stable epimeric amine in each case. It is not evident why the stereochemistry of reduction of anils and oximes should differ, however. 

Camphor oxime (1,7,7-trimethyl-2-norbomanone oxime) C10H17NO —164.0 2... 

Fragmentations of oximes of bicyclic compounds, e.g. camphor oxime, have been extensively studied, as the products can be used as chiral intermediates in enantiospecific syntheses. 

Electrochemical reductions of camphor oxime (R = Me) and norcamphor oxime (R = H) at a mercury cathode proceed with a high degree of diastereoselectivity (equation 3) . The products are in fact of opposite stereochemistry to those formed in dissolving metal (sodium-ethanol) reductions of the oximes. 

Usually, electrochemical oxidative hydrolysis of ketoximes affords the corresponding ketones. Hence, 2-octanone (equation 13) and acetophenone were obtained from the corresponding ketoximes in 90% and 97% yields, respectively. However, camphor oxime was transformed into the ring-cleaved nitrile (equation 14). ... 

Beckmann rearrangement of 6-endo-chlorocamphor oxime (Vol. 7, p. 43) yields (220) and the cis- and frans-ring-fused (221), and camphor oxime rearranges with hydrazoic acid in polyphosphoric acid to yield (222). ... 

A microanalytical procedure was reported for determination of camphor (190). The method is based on the formation of camphor oxime. The oxime is subjected to acid hydrolysis and the resulting hydroxylamine reacted with formalin and... 

The condensation of 1,2-diamino-4-nitrobenzene with bornane-2,3-dione has been investigated.290 Catalytic hydrogenation of fenchone oxime (203 X = NOH) gives the imine (203 X = NH) exclusively, whereas camphor oxime gives only the exo-amine (204) reduction with di-isobutylaluminium hydride yields predominantly heterocyclic secondary amines thus (203 X = NOH) gives (205) as the major product together with (206) and (204) and its endo-isomer.291... 

Form Supplied in red solid prepared from optically pure d-camphor oxime in a five-step sequence (eq 1) reduction with sodium in n-amyl alcohol followed by fractional recrystallization of the resulting hydrochloride salts of bornylamines gives the endo-isomer in enantiomerically pure form treatment with phosgene and direct condensation of the isocyanate with (ethoxycarbonyl)hydrazine gives a compound which cyclizes upon treatment with base subsequent nitrogen dioxide oxidation furnishes (-)-en[Pg.145]

Camphoric oxime offers a very curious particular case, repre sented in Fig. 97. Whatever is the composition X of the liquid mixture, Adriani found its freezing-point constant and equal to 118. 8 the line C is here reduced to a straight line parallel to OX. 

Oxaziridines have been proposed as intermediates in the photo-Beckmann rearrangement of oximes. A reinvestigation of the photochemistry of (+)-camphor oxime (60) has revealed that the... 

Nitrosolysis of camphor ethyl acetal with ethanolic ethyl nitrite in sulphur dioxide yields the orthoester oxime (205) which is rapidly dehydrated by excess acetal to the orthoester nitrile which then reacts with sulphur dioxide to form the ester nitrile and diethyl sulphite.Further papers in this section include the full paper on ozonolysis of silyl ethers (Vol. 5, p. 33), another synthesis of camphor-enol trimethylsilyl ether (cf. Vol. 6, p. 41)/°° the conversion of camphor oxime with Grignard reagents into the corresponding imine with no aziridine formation/° the preparation of (206) by treating bornylene with trichloroacetyl isocyanate/ the oxidation of thiocam-phor to the 5-oxide and alkylation in the presence of thallium(i) ethoxide to a/S-unsaturated sulphoxides/ and the free-radical C-3 alkylation of camphor with alkenes. " ... 

There are regularly publications concerning the transformation of bomane derivatives [particularly camphor (40) oxime] to campholenyl derivatives, but there is no particular interest attached to them as syntheses of natural products. Nevertheless, we mention work on the Beckmann-type rearrangements of camphor oxime,and a route to campholenic alcohol (352) from the hydroxycamphene 353. "Y-Campholenol (354) has been identified in Tanacetum... 

While most reducing agents lead to the expected bornylamines as products of the reduction of camphor oxime (see above), diisobutylaluminum hydride is a notable exception, as a ring-enlarged amine, (1/ ,47 )-1.8,8-trimethyl-2-azabicyclo[3.2.1]octane (67) is obtained in high yield when starting with the oxime of (+ )-camphor16, It has been used as the lithium salt in enantioselective deprotonation and elimination reactions (Section C.). 

R,4R)-N-(tert-bMoxy-carbonylmethyl)-camphor imine (—)-camphor oxime 7 (-)- Ar-[(1 R,4if)-2-bornylidene]-glycine terr-butyl ester D.l.5.2.4. 5 F... 

In an attempt to prepare bornylamines by rhodium-catalysed hydro-silylation of camphor oxime, a 2-[1(2,2,3-trimethylcyclopentyl)]-... 

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