Camphoric acid anhydride

A special case of stereoelectivity has been encountered in polymerizing a racemic monomer with an optically active one. Minoura et al. (158) carried out the ring-opening copolymerization of propylene oxide with d-camphoric acid anhydride using diethyl zinc and triethyl amine as catalyst. It was found that the products were alternating copolymers which were optically active. The propylene oxide recovered from the copolymerization system was also optically active. An attempt to incorporate preferentially in a polyamide chain one of the optical antipodes of trans-cyclopropane-1,2-dicarbonyl chloride, by polycondensing this racemic monomer with optically active 1,2-propylene diamine failed (159). 

Let us also mention some asymmetric-selective copolymerizations with propylene oxide (PO) it could be expected that another chiral co-monomer would favor the asymmetric-selection of one of both co-monomers. Tsuruta etal.[ S 2i] reported the asymmetric-selection copolymerization of 3-phenyl-4-tetrahydrophthalic acid anhydride with PO (LXI). Minoura et al [152] described the alternating copolymerization of PO and d-camphoric acid anhydride with diethylzinc triethylamine as optically inactive initiator the... 

The most important group of derivatives for the amino function (Fig. 7-4) is the carbamate group, which can be formed by reactions with acids, acid chlorides or acid anhydrides. A series of chlorides as 2-chloroisovalerylchloride [1], chrysanthe-moylchloride [2] and especially chloride compounds of terpene derivatives (cam-phanic acid chloride [3], camphor-10-sulfonyl chloride [4]) are used. The a-methoxy-a-trifluoromethylphenylacetic acid or the corresponding acid chloride introduced by Mosher in the 1970s are very useful reagents for the derivatization of amines and alcohols [5]. 

The complete process was as follows camphoric anhydride from camphoric acid was reduced with sodium amalgam to campliolide, and this combined with potassium cyanide gave homocamphoric nitrile. The nitrile was hydrolysed, and the calcium salt of the resulting homocamphoric acid, on heating, gave camphor ... 

Camphoric Anhydride -> Campholide -> Homo-camphoric- Acid,... 

Camphoric anhydride is prepared by mixing camphoric acid (100 gms.) with acetic anhydride... 

Because the bridge holds the molecule in a fixed conformation, the cleaved diacid has to have a specific stereochemistry. There is no change at the stereogenic centres, so the reaction must give retention of configuration. We can confidently write the structure of camphoric acid with ris-CC H groups, but any doubt is dispelled by the ability of camphoric acid to form a bridged bicyclic anhydride. 

However, on recryBtalbzation from acetic anhydride, Q-hydroxy> camphoric acid gives the ocarreeponding -laotone direotly, and a imilar compound. is lantonized by acetyl chloride at room temperature. 

The results obtained with camphorquinone in -xylene are of particular interest since this reaction has been investigated 129> under otherwise identical conditions in the presence and absence of oxygen. In carefully degassed -xylene solution at 4358 A the major products were the 1,2-adducts 56 and 57 the quantum yield for disappearance of dione was 0.07. In air-saturated -xylene the quantum yield increased to 0.16, 56 and 57 were not formed, instead the products were camphoric acid (104) and camphoric anhydride (105). No explanation has been offered for the different course of reaction in benzene where cyclic lactones 106 and 107 were obtained 97). Intermediacy of the cyclic diacyl peroxide 108 has been suggested 97h It is tempting to speculate that the diacyl radical 109 may have been trapped by oxygen. 

Beilstein Handbook Reference) AI3-00753 Benzo-a-pyrone BRN 0383644 Caswell No. 259C CCRIS 181 Cinnamic acid, o-hydroxy-, 8-lKtone ois-o-Coumaric acid anhydride Coumarin cis-o-Coumarinic acid lactone Coumarinic anhydride Coumarinic lactone Cumarin EINECS 202-086-7 EPA Pesticide Chemical Code 127301 HSDB 1623 o-Hydroxycinnamic lactone 0-Hydroxyzimtsaure-lacton Kumarin NCI C07103 NSC 8774 Rattex Tonka bean camphor. Used in pharmaceuticals as a flavorant. Crystals mpo 71" bp = 301.7 d O = 0.936 Xm = 273, 311 nm (e = 11200, 6710, MeOH) moderately soluble in H2O, EtOH, more soluble in EtzO, CHCI3, C5H5N. Alfa Aesar Rhodia Inc. Rhodia Organique Fine Ltd. 

Oxidation of camphor with nitric acid opens the six-membered ring, affording cis-and irarw-camphoric acid. Sulfonation of camphor with concentrated sulfuric acid and acetic anhydride selectively yields 10-camphorsulfonic acid. 

Chromic(VI) acid Acetic acid, acetic anhydride, acetone, alcohols, alkali metals, ammonia, dimethylformamide, camphor, glycerol, hydrogen sulflde, phosphorus, pyridine, selenium, sulfur, turpentine, flammable liquids in general... 

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. ... 

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