Aschan

Isopinene is a name which has been applied to at least two terpenes. Of these the earliest so-named is that isolated by Aschan by decomposing the liquid chlorides obtained in the process of preparing pinene hydrochloride, by the action of bases. He thus obtained a hydrocarbon which he termed pinolene, Cj Hj,., boiling at 145° to 146°. By converting... 

Zelinsky, apparently overlooking Aschan s isopinene, has improperly appropriated the same name to a quite different terpene. 

It is possible, however, that camphene hydrochloride is not a uniform body, but that some of the terpene suffers some rearrangement in the molecule by the action of hydrochloric acid, and that the hydrochloride consists of a mixture of a-camphene hydrochloride and /8-camphene hydrochloride there is, however, no evidence to suggest that camphene itwlf is a mixture of two terpenes, so that the two camphenes are not known to exist. Aschan obtained an alcohol, camphene hydrate, by acting on camphene hydrochloride with milk of lime, a reagent which does not produce molecular rearrangement in the terpene nucleus. 

Santene has also been examined by Aschan. The following are the characters of the purest specimens which have been isolated from sandalwood and Siberian nine oils —... 

Camphene hydrate is a tertiary alcohol, and a study of its characters and method of preparation caused Aschan to consider that it is improbable that borneol and isoborneol are stereoisomeric, but that they probably have different constitutional formulae. 

When the terpene a-fenchene (isopinene) is hydrated by means of acetic and sulphuric acids, it yields an isomer of fenchyl alcohol, which is known as isofenchyl alcohol (q.v.), and which on oxidation yields iso-fenchone, as fenchyl alcohol yields fenchone. The two ketones, fenchone and isofenchone, are sharply differentiated by isofenchone yielding iso-fenchocamphoric acid, Cj Hj O, on oxidation with potassium permanganate, which is not the case with fenchone. According to Aschan,i the hydrocarbon found in turpentine oil, and known as /9-pinolene (or cyclo-fenchene—as he now proposes to name it), when hydrated in the usual manner, yields both fenchyl and isofenchyl alcohols, which on oxidation yield the ketones fenchone and isofenchone. According to Aschan the relationships of these bodies are expressed by the following formulae —... 

Because both enantiomers, (+) and (-)-camphoric add, are available by oxidation either from natural (+)-D-camphor or from natural (-)-L-borneol, both enantiomers of camphanoyl chloride can be prepared conveniently.3 5 The corresponding enantiomers of camphanic acid were described for the first time by Wreden6and Aschan.7 The three-step procedure, described above is an adaptation of procedures described by Aschan,8 Zelinsky et al.,9 Meyer et al.,10 and Gerlach.3... 

The fact that the existence of asymmetric C-atoms is neither necessary nor sufficient for chirality was pointed out in 1902 by Aschan 21> in his criticism of van t Hoff s concept. He used the examples of meso-tartaric acid 10 and the achiral trioxiglutonic acid 11 to demonstrate that asymmetric C-atoms are not sufficient for chirality, and example 72 shows that they are also not necessary. 

The critical argument of Aschan that asymmetric C-atoms are not necessary for chirality, e.g., of 12, does, in fact, not pertain to van t Hoff s concept. This latter involves only the assumption that the combi-... 

D autres auteurs ont du recourir a la forme methylenecarbonique pour expliquer des phenomenes ou reactions particulieres, en premiere ligne Fisomerisation de Facide camphorique decrite par Aschan,... 

The first published report of the isomerization of a saturated hydrocarbon appeared in 1902, when Aschan reported1 that cyclohexane undergoes isomerization to methylcyclopentane with aluminum chloride. Later researchers were, however, unable to repeat this work, and it was not until 1933 that their failures were, as discussed subsequently, explained by Nenitzescu and coworkers.2 3... 

The use of mixtures of glycerol and formic acid for the preparation of allyl derivatives (allyl ch oride and allyl formate) has recently been described by Aschan.2 Allyl alcohol has also been isolated from crude wood alcohol.3 A special method for titrating allyl alcohol has been described.4... 

Van der Leeuw S.E. and Aschan-Leygonie C. (2000). A long-term perspective on resilience... 

In order to determine the camphor content of essential oils (which contain no other carbonyl compounds) the gravimetric determination proposed by Aschan (138) may be employed ... 

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