Camphoric acid, from camphor

Lanthanide /3-diketonates containing fluorinated chiral camphor-derived ligands (61, M = Pr, Eu, Er, Yb, R = Mef, n-Prf) form highly coordinated 14 complexes with zwitterionic, unprotected phenylalanine, leucine, and other amino acids under neutral conditions. This allows extraction of the amino acids from their neutral aqueous solutions into dichloromethane phases . 

Inactive malonic, fumaric, and maleic acids from the active malic acid inactive succinic and tartronic acids from the active tartaric acid inactive cymene from active camphor, etc. 

Camphor had been prepared from camphoric acid by Haller. Komppa synthesised camphoric acid from dimethylglutaric ester and from it obtained camphor. Perkin and J. F. Thorpe independently synthesised camphoric acid. When Komppa (1909) published the details of his synthesis, Thorpe and G. L. Blanc doubted its validity, but later confirmed that Komppa was correct. The formation of camphene from bornyl chloride involves what is called a Wagner-Meerwein rearrangement. ... 

Vauquelin, partly in collaboration with Fourcroy, discovered several important organic compounds. They distinguished a number of proximate constituents Yourcroy %principes immediats) in vegetables, such as acids, oils, camphor, gum, resin, tannin, starch, fibre, cork, caoutchouc, and extractive (a product of extraction with cold water and evaporation). Several definite compounds which had previously been obtained but the existence of which was in doubt were confirmed. Among these was malic acid and its salts. Sodium malate (with other salts of organic acids) was obtained by Donald Monro in 1767 and the acid from apples by Scheele in 1785 (see p. 232). The acid and its salts were studied by Fourcroy and Vauquelin. Vauquelin showed that the sorbic acid isolated from mountain-ash berries by Donovan is malic acid (the modern sorbic acid is a different substance) Vauquelin s elementary analysis of malic acid was inaccurate. 

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. 

By oxidation with permanganate it forms pinonic acid, C,oH,<503, a monobasic acid derived from cyclobutane. With strong sulphuric acid it forms a mixture of limonene, dipentene, terpinolene, terpinene, camphene and p-cymene. Hydrogen chloride reacts with turpentine oil to give CioHijCl, bomyl chloride, artificial camphor . 

The theory of sublimation, t.e. the direct conversion from the vapour to the sohd state without the intermediate formation of the liquid state, has been discussed in Section 1,19. The number of compounds which can be purified by sublimation under normal pressure is comparatively small (these include naphthalene, anthracene, benzoic acid, hexachloroethane, camphor, and the quinones). The process does, in general, yield products of high purity, but considerable loss of product may occur. 

First wash with a volume of Glacial Acetic Acid equal to the amount of Sassafras Oil being processed. This will remove Euge-nol, Pinene and Camphor from the oil. 

The isoprene unit exists extensively in nature. It is found in terpenes, camphors, diterpenes (eg, abietic acid), vitamins A and K, chlorophyll, and other compounds isolated from animal and plant materials. The correct stmctural formula for isoprene was first proposed in 1884 (7). 

Most synthetic camphor (43) is produced from camphene (13) made from a-piuene. The conversion to isobomyl acetate followed by saponification produces isobomeol (42) ia good yield. Although chemical oxidations of isobomeol with sulfuric/nitric acid mixtures, chromic acid, and others have been developed, catalytic dehydrogenation methods are more suitable on an iadustrial scale. A copper chromite catalyst is usually used to dehydrogenate isobomeol to camphor (171). Dehydrogenation has also been performed over catalysts such as ziac, iadium, gallium, and thallium (172). 

The present method is adapted from that of Loven. The resolution has been carried out with d-a-bromocamphor-TT-sulfonic acid (f-form) 2.3 with /-and d/-malic acids (d- and /-forms) with /-quinic acid and d-tartaric acid (d- and /-forms) and with d- and /-6,6 -dinitrodiphenic acids (d- and /-forms). Methods employing d-benzyimethylacetyl chloride, d-oxymeth-ylenecamphor, /-quinic acid, and d-camphoric anhydride are of theoretical interest only. The d/-amine is not resolved by the active camphor-lo-sulfonic acids or mandelic acids. ... 

Camphor was originally obtained from the camphor tree Lauras eamphora in which it appeared in the optically active dextro-rotary form. Since about 1920 the racemic ( ) mixture derived from oil of turpentine has been more generally used. By fractional distillation of oil of turpentine the product pinene is obtained. By treating this with hydrochloric acid, pinene hydrochloride (also known as bomyl chloride) may be produced. This is then boiled with acetic acid to hydrolyse the material to the racemic bomeol, which on oxidation yields camphor. Camphor is a white crystalline solid (m.p. 175°C) with the structure shown in Figure 22.3. 

This study also demonstrated the importance of choosing an appropriate acid to effect the cyclization of 21 in the desired direction. For example, the use of neat TFA for 72 h produced mainly 22, whereas the prevailing product from the reaction induced by camphor sulfonic acid (CSA) was identified as the other possible product 25. In an equilibration experiment, 25 underwent treatment with TFA for 72 h, giving a 12 1 mixture of 22 and 25, whereas compound 22 equilibrated to... 

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 —... 

Esters of bomeol are obtained by the action of dry oxalic acid on turpentine under suitable conditions. From these, borneol is obtained by saponification and is oxidised to camphor. Some other acids produce a similar result, as, for example, salicylic and chlorobenzoic acids. 

It results, artificially, from the treatment of carvone by potash or phosphoric acid, and by heating camphor with iodine. 

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,... 

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