878-13-7Relevant articles and documents
Exaltone (=Cyclopentadecanone) from Isomuscone (=Cyclohexadecanone), a one-C-atom ring-contraction methodology via a stereospecific favorskii rearrangement: Regioselective application to (-)-(R)-muscone
Chapuis, Christian,Robvieux, Fabrice,Cantatore, Carole,Saint-Leger, Christine,Maggi, Laurent
, p. 428 - 447 (2012/05/07)
Treatment of cyclohexadecanone (1g; with I2 (2.2 mol-euqiv.) and KOH in MeOH) furnished the unsaturated (Z)-ester 2g in 83% yield, via a stereospecific Favorskii rearrangement (Scheme 1). Further treatment with 3-chloroperbenzoic acid (m-CPBA) afforded the unreported epoxy ester 3g (88% yield), which was cleaved in 33% yield to Exaltone (=cyclopentadecanone; 1f) with NaOH in MeOH/H2O and then HCl at 65°. This methodology was similarly extended to higher (C17) and lower (C15 to C11) cyclic ketone analogues, as well as regioselectively to (-)-(R)-muscone (5c) and homomuscone (5f) (Scheme 2). Olfactive properties of the corresponding macrocyclic 1-oxaspiro[2,n]alkanes and -alkenes 4 and 8, resulting from a Coreyi-Chaykovsky oxiranylation, are also presented. Copyright
Gene encoding cyclododecanone monooxygenase
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, (2008/06/13)
The invention relates to a new strain of Pseudomonas putida (designated as HI-70) and to the isolation, cloning, and sequencing of a cyclododecanone monooxygenase-encoding gene (named cdnB) from said strain. The invention also relates to a new cyclododecanone monooxygenase and to a method of use of the cyclododecanone monooxygenase-encoding gene.
The effect of pressure on cyclizations. The ring-size dependent reaction volumes of the cyclization of 1-alkenes to cycloalkanes. Experimental measurement of activation and reaction volumes of the intramolecular diels - Alder reaction of 1,3,8-nonatriene and 1,3,9-decatriene. Temperature dependence of activation and reaction volumes
Diedrich, Matthias K.,Kl?rner, Frank-Gerrit
, p. 6212 - 6218 (2007/10/03)
The volumes of reaction determined for the hypothetical cyclization of 1-alkenes to cycloalkanes decrease continUOusly from the formation of cyclopropane (ΔV(R) = -5.5 cm3 mol-1) up to the formation of cyclodecane (ΔV(R) = -32.3 cm3 mol-1) and seem to be constant for the larger rings. The analysis of the packing coefficients (η = V(w)/V) leads to the conclusion that this ring-size dependent decrease in volume results from the different packing of cyclic and acyclic compounds rather than from the changes in their intrinsic molecular volumes. The investigation of the intramolecular Diels-Alder reactions of (E)-l,3,8-nonatriene (E)-1 and (E)- 1,3,9-decatriene (E)-2 leading to the bicyclo[4.3.0]nonenes cis- and trans-4 (ΔV≠/ΔV(R) [cm3 mol-1] -24.8/-32.0 and -24.8/-28.5, respectively) or bicyclo[4.4.0]decenes cis- and trans-6 (-37.6/-45.4 and -35.0/-37.4, respectively) confirms the ring-size dependence of the activation and reaction volumes. The dependence of the effect of pressure from the number of newly forming rings is illustrated with the thermolysis of (Z)-1,3,8- nonatriene (Z)-1 in which an intramolecular Diels-Alder reaction leading to bicyclo [4.3.0]nonene cis-4 competes with a sigmatropic [1,5] hydrogen shift leading to (E,Z)-1,5,7-nonatriene 7. The use of high pressure causes a reversal of selectivity.