Endo-borneol

A series of cyanoacetic acid derivatives 96 (94TA1435, 95TA255) was used for the introduction of a chiral moiety into position 3 of a pyran ring Oppolzer s sultam (a), (—)-menthol (b), (IS)-endo-(-)-borneol (c), ethyl (S)-(—)-lactate (d), diisopropylidene-o-glucofuranose (e). Both Methods 1 and... 

R-2-endo-Borneol [464-43-7] M 154.3, m 208° [a] +15.8° (in EtOH). Crystd from boiling EtOH (charcoal). 

Fluoroboric acid supported on silica (HBF4-silica) has recently been found to be a highly efficient catalyst in the protection of various functional groups. Structurally diverse alcohols, phenols, thiophenols, and anilines can be acylated under solvent-free conditions at room temperature.669 Even acid-sensitive tertiary alcohols (1-alkylcyclo-hexanols) and sterically hindered compounds, such as endo-borneol, give the acylated products in high yields. A triflic acid-silica catalyst also shows high activity in the (9-acetylation with Ac20 of alcohols and phenols.359... 

Borneo camphor Bomeol. See DL-Bomeol (-)-Borneol Bomeol, (1S,2R,4S)-(-)- (-)-(1S,4S)-Borneol [(1S)-endo-(-)-Borneol. SeeL-Borneol... 

Synonyms Bicycio (2.2.1) heptan-2-ol, 1,7,7-trimethyl-, acetate, endo- Borneol acetate levo-Bomyl acetate Bornyl acetic ether ... 

CAS 5655-61-8 EINECS/ELINCS 227-101-4 Synonyms Bicycio [2.2.1] heptan-2-ol, 1,7,7-trimethyl-, acetate, (1S-endo)- Borneol, acetate, (1S,2R,4S)-(-)- (-)-Bornyl acetate L-Born-2-yl acetate L-a-Bornyl acetate endo-(1S)-1,7,7-Trimethylbicyclo [2.2.1] hept-2-yl acetate Empirical C12H20O2... 

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. 

Interestingly, both endo- and exo-borneol are oxidized to camphor at the same rate, despite the enormous difference in the steric environment of these two alcohols (Table V, Entries 9 and 10). 

SYNS BAROS CAMPHOR BHIMSALM CAMPHOR BICYCLO(2.2.1)HEPTAN-2-OL, 1,7,7-TRIMETHYL-, endo-(9CI) 2-BORNANOL, endo- BORNEO CAMPHOR D trans-BORNEOL BORNEOL (DOT) BORNYL ALCOHOL CAMPHANE, 2-HYDROXY- 2-CAMPHANOL CAMPHOL DRYOBALANOPS CAMPHOR 2-HYDROXYCAiMPHANE MALAYAN CAMPHOR SUMATRA CAMPHOR endo-1,7,7-TRIMETHYL-BICYCLO(2.2.1)HEPTAN-2-OL... 

The first examples of an asymmetric Diels-Alder reaction of a non-chiral diene and a dienophile catalyzed by a chiral Lewis acid were reported by Koga and coworkers in 1979 (Sch. 1 and 16) [3]. The catalysts 4,142 and 143 were prepared from (-)-menthol, (+)-neomenthol and (+)-borneol. The reaction of methacrolein and cyclopentadiene mediated by catalyst 4 gave a 98 2 mixture of exo to endo products and upon separation of these diastereomers by chromatography the exo product 3 was obtained in 69 % yield and 72 % ee. The exo .endo ratios for the other reactions in Sch. 16 were not reported. Low asymmetric induction was observed for acrolein and methyl acrylate with all three catalysts. Moderate induction was observed in the reaction of methacrolein with catalyst 4, and with catalyst 142, but in the latter the enantiomer of 3 was the predominant product. The reaction of methyl acrylate with cyclopentadiene mediated by 10 mol % catalyst 4 was also reported by Kobayashi, Matsumura and Furukawa to give the cycloadduct 141 in 2.9 % ee at 30 °C [37]. These workers also reported that catalyst 4 will give optically active product from the reaction of cyclopentadiene and acrylonitrile, although the optical yield was not determined. 

Metal-ammonia reduction of bicyclo[2,2,l]heptanones has been examined by Coulombeau and Rassat, who point out that the conformationally more stable forms of substituted alcohols are the exo-isomers in the case of norbornan-2-ol and the 1-methyl homologue, but the endo-isomers in the case of borneol (1,7,7-trimethyl) and fenchol (1,3,3-trimethyl). The same authors have also examined the reduction of camphorquinone [2,3-dioxo-bornane, (249)] with... 

Bicyclic cyclopropyl compounds are anodically dimethoxylated to give stereoisomeric cis and trans) cyclopropane ring-opened products, as in Eq. (48) [322]. Shono and coworkers [323] reported a different type of ring-opening reaction of a cyclobutyl compound through anodic methoxylation. They also found that anodic oxidation of borneol and isoborneol in methanol resulted in a rearrangement to provide methoxylated stereoisomeric products with the same endo-exo ratio, as in Eq. (49) [324] ... 

Chlorohydroboration-oxidation of camphene yields a 3 1 endo exo mixture of (185 X = CH20H), and bornylene is converted into a mixture of borneols and epiborneols, the -isomers predominating in each case. ... 

Amination of borneol with ammonia over an Fe-, Cu- and Al203-containing catalyst afforded bornylamines mainly as endo isomers (Scheme 4) [11]. 

Microbial oxidation of (-i-)-bornyl acetate (to 5-exo- and 5-endo-hydroxy-borneol) using Helminthosporium sativum is more efficient and regiospecific than that reported previously (Vol. 8, p. 51) with the enantiomer, in contrast to the conversion of (+)- and (-)-bornyl acetate, using Fusarium culmorum, into 5-exo-hydroxybornyl acetate. 

Bornanol, endo- Borneo camphor Borneol DL-Borneol trans-Borneol Bornyl alcohol 2-endo-Bornyl alcohol Camphane, 2-hydroxy- 2-Camphanol Camphol CCRIS 7300 Dryobalanops camphor EINECS 208-080-0 FEMA No. 2157 HSDB 946 2-Hydroxybornane 2-Hydroxycamphane 2-Hydroxy-1,7,7-trimethylnor-bornane, endo- Malayan camphor Sumatra camphor 1,7,7-Trlmethyl-bicyclo(2.2.1)heptan-2-ol, endo- UN1312. A terpene from Dryobalanops camphora used in perfumery, in celluloid manufacture, and in medicine as an anSseptic. Crystals mp = 208" bp = 212" insoluble in H2O, soluble in organic solvents LD50 (rat orl) = 500 mg/kg. 

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