Carboxyl Carvone

The carboxylic acid 150 (Scheme 10.15) was prepared from commercial (-)-carvone (68) via a chemoselective reduction of the terminal olefin using tris... 

Sodium dithionite under nitrogen at 80 °C in a water/benzene mixture and in the presence of a phase transfer catalyst reduces dienoic carboxylic acids and esters in a 1,6-mode. Enones such as isopho-rone, pulegone and carvone are similarly reduced to the saturated ketones. Citral and dimethyl maleate are also reduced in a 1,4-manner in moderate yield. ... 

E. Lee and co-workers demonstrated that the chlorohydrin derived from (+)-carvone undergoes a stereoselective Favorskii rearrangement to afford a highly substituted cyclopentane carboxylic acid derivative. This intermediate was then converted to (+)-dihydronepetalactone. When the THP-protected chlorohydrin was treated with sodium methoxide in methanol at room temperature, the rearrangement took place with excellent stereoselectivity (10 1) and high yield. Interestingly, the major product was the thermodynamically less stable cyclopentanecarboxylate. 

In order to determine the structure of the photochemical rearrangement product of carvone camphor in methanol, and to prove its structure, the research team of T. Gibson subjected the bicyclic carboxylic acid product to a degradation sequence, which commenced with the HVZ reaction, followed by dehydrohalogenation, dihydroxylation and glycol cleavage. 

Selected from numerous other, apparently randomly studied, reactions are carboxylation of menthol or menth-l-ene at C-l, C-3, C-4, and C-8 on treatment with C0-BF3-C1CH2C02H,412 coupling of limonene at C-2 and C-4 to xylenols in the presence of Amberlite IR-120 resin,413 dimerization (C-3 to C-3 linkage) of carvone induced by FeCl3,414 and the aromatization observed in the BF3-catalysed reaction of terpinolene and tetrahydrogeraniol to give cymen-8-yl tetrahydrogeranyl ether.415... 

Carbon suboxide, 52 Carbonylation, 148, 149, 216 Carbonyl chlorofluoride, 48, 54 Carbonyl cyanide, 60-61 N,N -Carbonyldiimidazole, 61 1,1-Carbonyldi-l,2,4-triazole, 61 N-Carbonylsulfamic acid chloride (N-Carbonylsulfamyl chloride), 61 Carboxamides, 270 Carboxamine-N-sulfochlorides, 70 p-Carboxybenzenediazonium chloride, 62 p-Carboxybenzenesulfonazide, 62 Carboxylation, 15, 16 Carboxylic acid anhydrides, 133 Carboxylic acid N,N-dimethylamines, 153 Carboxylic anhydrides, 409-410 p-Carboxyphenylhydrazones, 62 Cardenolides, 130, 131 (S-Carotene, 19 /-Carvone, 451, 452 i//-Caryophyllene, 149, 150 Catechol, 65, 233 Catechol amines, 159 Catechyl phosphorus tribromide, 63 Catechyl phosphorus trichloride, 63 Cis-Cecropia juvenile hormone, 261 Cedrene, 234, 235 a-Cedrene, 349 /3-Cedrene, 349 Cendranoxide, 234, 235 Cephalosporin C, 48 Ceric ammonium nitrate, 63-65 Ceric sulfate. 65 Cesium fluoride, 346 trans-Chalcone oxide, 422 Chalcone phenylhydrazones, 257, 258 Chalcones, 406 Chloramine, 65-66, 69 Chloranil, 66-67, 113, 116, 401,454... 

Ihtf combination of MejSiBr with an oxi-h J RaN MnO it converts carvone to the iturated carboxylic acids is accomplished... 

---