Bornane

Camphor, synthetic, see Bornan-2-one Caprolactam Dust Vapour... 

A remarkable effect of the reaction temperature on the enantioselectivity of the addition of butyllithium to benzaldehyde was found with polystyrene-bound cvs-enofo-S-dimethylamino -(benzyloxy)bornane (8)12. When the soluble monomeric ligand 9 was tested, the enantioselectivity increased with decreasing temperature (53% ee at — 78 C). In contrast, the polymer-bound chiral additive 8 showed an optimum at — 20 C (32% ee). Although the enantioselectivity of this addition reaction is low, an advantage of a polymer-bound chiral auxiliary is that it can be removed by a simple filtration. 

Asymmetric hefera-Diels-Alder addition of 1 -methoxybuta-1,3-diene to (2R)-N-pyruv-oyl-and (2R)-N-(phenylglyoxyloyl)bornane-10,2-sultam [69]... 

C9H15NO2 112843-64-8) see Tropenziline bromide ej o-2-(6-methoxy-3,4-xylyl)bornane (CiijHjsO 31467-21-7) see Xibomol methyl 4-acetamido-5-bromo-2-methoxybenzoate (C, H (,BrN04 89481-86-7) see Bromopride methyl 4-acetamido-5-chloro-2-methoxybenzoate (C,iHijClNO 4093-31-6) see Clebopride Metoclopramide... 

Toxaphene is a complex mixture of compounds prepared by chlorinating camphene, and contains several hundred polychlorinated bornanes. After incubation with Sulfurospirillum (Dehalospirillum) multivorans only the hexa- (B6-923) and the heptachlorinated (B7-1001) remained. The nonachlorinated congener B9-1679 could be transformed by preferential dechlorination of the em-dichloro groups with formation of the heptachlorinated B7-1001 (Ruppe et al. 2003). Further examination showed that this congener could be dechlorinated to penta- and hexachlorinated bornanes (Ruppe et al. 2004). 

The catalysis has been extended for use with chiral boronates and those from the phenyl-substituted bornane diol derivatives A and B54 have been found to be particularly effective.55... 

Based on this, asymmetric hydroamination was developed using [Ir(C2H4)4Cl] or lr(coe)2Cl]2 (coe = cyclooctene) with chiral diphosphines to give complexes (57)-(61) (Scheme 40). While (57) afforded only a low yield and poor enantiomeric excess (51% 2S) of exo-2-(phenylamino)nor-bornane, addition of up to one equivalent of fluoride ion gave a six-fold increase in chemical yield (from 12% to 81%) and a reversal of enantioselectivity. In the case of (60), addition of four equivalents of fluoride led to an ee of 95 % The role of fluoride in these reactions has still not been explained satisfactorily.175... 

Treatment of sterically-crowded selones possessing substituted bornane skeletons with chloramine-T afford several products derived from intermediary selone Se-imides (Scheme 37). Direct observation of the intermediates was done by NMR monitoring at low temperature.240... 

Synonyms AI3-18783 Alphanon 2-Bornanone DL-Bornan-2-one BRN 1907611 BRN 3196099 2-Camphanone DL-Camphor Camphor-natural Camphor-synthetic Caswell No. 155 EINECS 200-945-0 EINECS 207-355-2 EINECS 244-350-4 EPA pesticide chemical code 015602 Formosa camphor Gum camphor Iphanon Japan camphor 2-Keto-l,7,7-trimethyl-norcamphane Laurel camphor Matricaria camphor Norcamphor 2-Oxobornane Root bark oil Sarna Spirit of camphor Synthetic camphor l,7,7-Trimethylbicyclo[2.2.1]heptan-2-one 1,7,7-Trimethylnorcamphor UN 2717. 

In bridged ring compounds, rings share more than two atoms, and the bridge can consist of one or more atoms. We have already met an example in bornane (see Section 3.3.2), which we used as an illustration of how a cyclohexane ring can be forced into a boat conformation to achieve the necessary bonding. 

When we move on to camphor, a ketone derivative of bornane, we find this can exist in two enantiomeric forms because the plane of symmetry has been destroyed. Nevertheless, there are only two configurational isomers despite the presence of two chiral centres bridging does not allow the other two variants to exist. 

A similar observation was made in the transformations of the nor-bornane and norbornene diexo-tm d azetidinones 300 (X = CH2CH2, CH=CH) to dicxo-methanoquinazolinediones 302 (87T1921). 

Bornene has been prepared from the reaction of 2-bromo-bornane-3-carboxyIic acid with aqueous sodium bicarbonate,6 by pyrolysis of isoborneol methyl xanthate,7 and by the j8-elimination of hydrogen chloride from bornyl chloride with sodium alkoxides in various solvents.2... 

Langlois and co-workers (179) found the same exo stereochemical preference through double asymmetric induction of a related ene-lactone (1 )-145 with their well-explored and efficient camphor-derived oxazoline nitrone (150-146 (Scheme 1.32). They found the cycloaddition components form a matched pair and allowed kinetic resolution of the racemic lactone in up to 70% enantiomeric excess (ee). They suggest the selectivity for exo adduct 147 arises through destabilization of the endo transition state by a steric clash between dipolarophile ring hydrogens and the bornane moiety. 

After these modest but promising beginnings, this strategy received fresh impetus with the use of the rigid bornane derivatives as auxiliaries117. 

Amides prepared from both enantiomers of 10,10-dimethyl-4-aza-3-thiatricyclor5.2.1.01,5ldecane 3,3-dioxide (bornane-10,2-sultam) can be used in diastereoselective alkylation reactions to give high chemical yields and high diastereomeric ratios of monoalkylation products5,6,10,16-19. 

V-Acylbornane-l 0,2-sultams 2 are prepared from the bornane-10,2-sultam 1 via NH-deproto-nation with sodium hydride and subsequent acylation with a suitable acid chloride. 

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