Of -camphor

Borneol and isoboineol are respectively the endo and exo forms of the alcohol. Borneol can be prepared by reduction of camphor inactive borneol is also obtained by the acid hydration of pinene or camphene. Borneol has a smell like camphor. The m.p. of the optically active forms is 208-5 C but the racemic form has m.p. 210-5 C. Oxidized to camphor, dehydrated to camphene. 

Ordinary commercial camphor is (-i-)-cam phor, from the wood of the camphor tree. Cinnamonum camphora. Camphor is of great technical importance, being used in the manufacture of celluloid and explosives, and for medical purposes, /t is manufactured from pinene through bornyl chloride to camphene, which is either directly oxidized to camphor or is hydrated to isoborneol, which is then oxidized to camphor. A large number of camphor derivatives have been prepared, including halogen, nitro and hydroxy derivatives and sulphonic acids. 

Epicamphor is prepared from methyl-( + )-bornylene-3-carboxylate, and does not occur naturally. The smell of epicamphor differs slightly from that of camphor. 

Light oil of camphor is an almost colourless fraction containing a small amount of camphor, about 30% of cineole and the remainder terpenes. 

Dark oil of camphor consists very largely of safrole. 

The following oxidation of camphor to camphor-quinone illustrates the oxidising action of selenium dioxide, and readily gives a crystalline product. 

Place a mixture of 5 g. of camphor, 6 g. of powdered selenium dioxide and 5 ml. of acetic anhydride in flask fitted with a reflux water-condenser. Heat the flask in an oil-bath for 3 hours at 140-150 so that gentle boiling occurs shake the mixture from time to time. 

III. Depression of the Freezing-point of Camphor (Rast s Method). 

DETERMINATION OF MOLECULAR DEPRESSION CONSTANT OF CAMPHOR, using Solute of Known Molecular Weight (Naphthalene, Ck,Hj). 

This value is the Molecular Depression Constant (K) of Camphor. 

DETERMINATION OF MOLECULAR WEIGHT OF A GIVEN SUBSTANCE, e.g., ACETANILIDE, using the above Molecular Depression Constant of Camphor. 

Paulsen, M.D. Orn stein, R.L. A 175-psec molecular dynamics simulation of camphor-bound cytochrome p-45Proteins 11 184-204, 1991. 

The amount of camphor in an analgesic ointment can be determined by GC using the method of internal standards. " ... 

Camphor Manufacture. Camphor is obtained both naturally and synthetically. Natural camphor is obtained from the wood of the camphor tree, Cinnamormum camphora which grows ia China and Japan. The camphor is isolated by combination of steam distillation, filtration, distillation, and sublimation (169). Natural camphor is the (+)-camphor, whereas synthetic camphor is racemic both products are recognized by the USP. In 1995, the price of synthetic camphor was 7.15/kg (45). In 1992—1993, the total production of synthetic camphor ia India was 3800 t, which is estimated to be about 40% of the world consumption (170). The largest single use (80%) of camphor is for religious purposes ia Asian countries. 

The rather unexpected plasticising effect of camphor was first appreciated by Hyatt over a hundred years ago and, in spite of all that has been learned about polymers since then, no superior plasticiser has yet been discovered. 

It is not feasible here to go in any detail into the history of processing methods let it suffice to point out that that history goes back to the Victorian beginnings of polymer technology. Thus, as Mossman and Morris (1993) report, the introduction of camphor into the manufacture of parkesine in 1865 was asserted to make it possible to manufacture more uniform sheets than before. Processing has always been an intimate part of the gradual development of modern polymers. 

Since cbiral sulfur ylides racemize rapidly, they are generally prepared in situ from chiral sulfides and halides. The first example of asymmetric epoxidation was reported in 1989, using camphor-derived chiral sulfonium ylides with moderate yields and ee (< 41%) Since then, much effort has been made in tbe asymmetric epoxidation using sucb a strategy without a significant breakthrough. In one example, the reaction between benzaldehyde and benzyl bromide in the presence of one equivalent of camphor-derived sulfide 47 furnished epoxide 48 in high diastereoselectivity (trans cis = 96 4) with moderate enantioselectivity in the case of the trans isomer (56% ee). ... 

In a study of the nitrosation of camphor-3-glyoxylic acid (89), Chorley and Lapworth isolated a compound whose structure (90) has recently been clarified by Hatfield and Huntsman. Decarboxylation and ring expansion occur and the reaction is rationalized in the sequence 89 90. The buttressing effect of a methyl group on... 

The cyclized analog of meralluride is prepared by a similar synthesis. Thus, condensation of camphoric acid (42) (obtained by oxidation of camphor) with ammonia gives the bicyclic succinimide (44). Reaction with allyl isocyanate followed by ring opening and then reaction with mercuric acetate affords the mercury derivative (45) as the acetate rather than the hydroxide as above. Reaction with sodium chloride converts that acetate to the halide (46). Displacement on mercury with the disodium salt of thioglycollic acid affords the diuretic mercaptomerine (47). ... 

Camphor Quinone Monotosylhydrazone To 22 g (0.133 mole of camphor quinone in 150 ml of chloroform is added 26.1 g (0.14 mole) of p-toluenesulfonylhydrazide in one batch. The reaction vessel is protected with a drying tube and fitted with a magnetic stirrer, and the mixture is stirred at room temperature for 24 hours. The monotosyl-hydrazone is not isolated. 

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