Camphor preparation

Child protective closures are required for certain medicines, salicylates, paracetamol, iron tablets or capsules and camphor preparations (MCC Circulars 5/80, 9/80 and 10/84). 

Reut N A, Danusevich I K, Zakharevskii A S, Kuz mitskii B B, Kevra M K, Miklevich A V, Manukov E I, Reutsakaya G I, Sidorenko E R 1975 Toxicological properties of synthetic camphor prepared from pine tree oleoresins. Farmakol Toksikol Nov Prod Khim Sint Mater Resp Konf 3rd, 187... 

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. 

Me2C = CHCOCH= CMca- Yellow liquid having a camphor-like odour m.p. 28 C, b.p. 198-5°C. It is formed when propanone is saturated with HCl and allowed to stand. Resembles camphor in many of its properties and is a solvent for cellulose nitrate. Used to prepare diisobutyl ketone (reduction). 

In this preparation, the ( + ) or dextro-rotatory (natural) camphor or the ( ) or racemic (synthetic) camphor can be used. Perform the oxidation in a fume-cupboard. 

The structure of the bicychc monoterpene borneol is shown in Figure 26 7 Isoborneol a stereoisomer of borneol can be prepared in the labora tory by a two step sequence In the first step borneol is oxidized to camphor by treatment with chromic acid In the second step camphor is reduced with sodium borohydride to a mixture of 85% isoborneol and 15% borneol On the basis of these transformations deduce structural formulas for isoborneol and camphor... 

The first satisfactory photographic film was produced in 1888 when gelatin-dispersed microcrystals of silver haUde were coated on celluloid sheets (23). Within a year George Eastman prepared and marketed toU films on a base produced by dissolving nitrocellulose with camphor and amyl acetate in methanol (qv). 

Ma.nufa.cture. The preparation of sulfuryl chloride is carried out by feeding dry sulfur dioxide and chlorine into a water-cooled glass-lined steel vessel containing a catalyst, eg, activated charcoal. Alternatively, chlorine is passed into Hquefted sulfur dioxide at ca 0°C in the presence of a dissolved catalyst, eg, camphor, a terpene hydrocarbon, an ether, or an ester. The sulfuryl chloride is purified by distillation the commercial product is typically 99 wt % pure, as measured by ASTM distillation method D850. 

Camphor [126-04-5] (11), menthol [89-78-1] (12), and thymol [89-83-8] (13) ate used in topical over-the-counter cough and cold preparations. Camphor is isolated from the camphor tree, Cinnomomum camphora T. Nees Eherneier, or prepared synthetically from a-pinene or isobomeol. About 75% of the camphor sold in the United States is synthetic. Menthol, commercially the most important terpene alcohol, is obtained by crysta11i2ation from... 

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). ... 

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). ... 

Cadinene owes its name to its occuiTence in considerable quantity in oil of cade—which, of course, is not a true essential oil, but the product of destructive distillation. It is found in numerous essential oils, including those of patchouli, savin, galbanum, camphor, cedar wood. West Indian santal, juniper, and many others. Cadinene is best prepared as follows —... 

Givaudan Co., however, compare the properties of piperitone with those of the ketone prepared synthetically by Wallach, and discovered in Japanese peppermint oil by Schimmel and later in camphor oil by Bchimmel, and finally in the oil of Cymhopogon sennaarensis by Roberts,"... 

Camphor, Cj HjgO, occurs in the wood of the camphor tree Laurus camphora) as dextro-camphor. This is the ordinary camphor of commerce, known as Japan camphor, whilst the less common laevo-camphor is found in the oil of Matricaria parthenium. Camphor can also be obtained by the oxidation of borneol or isoborneol with nitric acid. Camphor may be prepared from turpentine in numerous ways, and there are many patents existing for its artificial preparation. Artificial camphor, however, does not appear to be able to compete commercially with the natural product. Amongst the methods may be enumerated the following —... 

Pinene hydrochloride is prepared in the usual manner from turpentine, and this is allowed to react with acetate of silver. Isobornyl acatate is formed, which is hydrolysed, and the isoborneol oxidised to camphor. Acetate of lead is also used, as is also acetate of zinc. 

Haller and Louvrier have prepared a number of homologues of camphor by heating the ketone in benzene solution with sodamide and alkyl iodides. The following are the characters of a number of these —... 

Sulfinic esters, aromatic, by oxidation of disulfides in alcohols, 46, 64 Sulfonation ot d,l camphor to d,l-10-camphorsulfomc acid, 45,12 Sulfoxides, table of examples of preparation from sulfides with sodium metapenodate, 46,79 Sulfur dioxide, reaction with styrene phosphorus pentachlonde to give styrylphosphomc diclilonde, 46,... 

Several methods for asymmetric C —C bond formation have been developed based on the 1,4-addition of chiral nonracemic azaenolates derived from optically active imines or enamines. These methods are closely related to the Enders and Schollkopf procedures. A notable advantage of all these methods is the ready removal of the auxiliary group. Two types of auxiliaries were generally used to prepare the Michael donor chiral ketones, such as camphor or 2-hydroxy-3-pinanone chiral amines, in particular 1-phenylethanamine, and amino alcohol and amino acid derivatives. 

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