2.4.7- Decatrienal

The intramolecular Diels-Alder reaction of 2-methyl-( , )-2,7,9-decatrienal catalyzed by the CBA catalyst 3 proceeds with the same high diastereo- and enantio-selectivity [5d] (Scheme 1.6). 

Brmsted acid-assisted chiral Lewis acid 8 was also applied to the intramolecular Diels-Alder reaction of an a-unsubstituted triene derivative. ( , )-2,7,9-Decatrienal reacts in the presence of 30 mol% of the catalyst to afford the bicyclo compound in high yield and good enantioselectivity [lOd] (Scheme 1.17). 

Intramolecular Diels-Aldet cyclizadons of fE -Tnitro-l,7,9-decatrienes under thermal con-didons and Lev/is acid conchdons lead to the formadon of decahn ring systems with excellent aiido selecdvity fEq 8 21 This strategy is used for preparing of the AB ring system of norzoanthamine "... 

The metathesis of acyclic alkadienes and higher polyenes may involve both inter- and intramolecular processes. An example of an intermolecular reaction is the conversion of 1,5-hexadiene into 1,5,9-decatriene and ethene ... 

Mutual metathesis of a cyclic and an acyclic alkene provides still more possibilities in synthesizing organic compounds. For instance, cycloalkenes are cleaved by ethene into a,co-dienes. The reaction of 1,5-cyclooctadiene with ethene gives 1,5,9-decatriene (18) norbornene reacts with 2-butene to yield 1,3-dipropenylcyclopentane (30) ... 

LP-DE also promotes and accelerates intramolecular Diels-Alder reactions of low reactive polyenones. The use of a catalytic amount of camphorsulfonic acid (CSA) further accelerates the cycloaddition and enhances the diastereo-selectivity [41]. Table 6.7 illustrates the effect of CSA on the intramolecular Diels-Alder reaction of 2-methyl-l,7,9-decatrien-3-one. 

Table 6.7 Intramolecular Diels-Alder reaction of 2-methyl-l,7,9-decatrien-3-one...

Detailed investigation of T. rotula and other diatom species revealed that 2,4-decadienal (24) and 2,4,7-decatrienal (27) represent only members of a structurally diverse class of oc, 3,y,6-unsaturated aldehydes found in several... 

Octatriene reacts further with butadiene in acetic acid by using 7r-allylic palladium complex as catalyst to give a mixture of acyioxydo-decatrienes (54). 

Butadiene-ethylene dimerization (example 3, Table II) has been shown to proceed via a croty 1-nickel complex formed by protonation (54). It should be observed at this point that it cannot be excluded that linear cooligomerization of butadiene with ethylene to give 1,4,9-decatriene... 

Decarboxylation catalysts for, 19 89 cycloamylose-catalyzed, 23 242-244 Decationation, 33 264-272 1,5,9-Decatriene, metathesis of, 24 134 1-Decene... 

Decatriene complexes with gold, 12 348 Decay method, of isotope half-life determination, 2 325... 

Anhydrous silver-olefin complexes are readily dissociable, low-melting, and variable in composition 92a, 176, 183). Cyclic olefins and polyolefins form stable complexes with silver nitrate or perchlorate, but again the Stoichiometry of the complexes varies considerably, sometimes depending on the conditions of preparation. The following types have been isolated [Ag(un)2]X (un = e.g., cyclohexene, a- and /3-pinene) ISO), [Ag(diene)]X diene = e.g., dicyclopentadiene 220), cyclo-octa-1,5-diene 50, 130), bi-cyclop, 2,1 ]hepta-2,5-diene 207), and cyclo-octa-1,3,5-triene 52), and [Ag2(diene)]X2 (diene = e.g., cyclo-octa-1,3- and -1,4-diene 180), bi-cyclo[2,2,l]hepta-2,5-diene 1) and tricyclo[4,2,2,0]-decatriene 10)). Cyclo-octatetraene (cot) forms three adducts with silver nitrate 52), viz., [Ag(cot)]NOs, [Ag(cot)2]N03, and [Ag3(cot)2](N03)3. On heating, the first two lose cyclo-octatetraene and all three decompose at the same temperature. From the stoichiometry of the above complexes it appears that the... 

Conjugated dienes can be dimerized or trimerized at their 1,4 positions (formally, 4 + 4 and 4 + 4 + 4 cycloadditions) by treatment with certain complexes or other transition-metal compounds.1088 Thus butadiene gives 1,5-cyclooctadiene and 1,5,9-cyclodo-decatriene.1089 The relative amount of each product can be controlled by use of the proper catalyst. For example, Ni P(OC6H4-o-Ph)3 gives predominant dimerization, while Ni(cyclooctadiene)2 gives mostly trimerization. The products arise, not by direct 1,4 to 1,4 attack, but by stepwise mechanisms involving metal-olefin complexes.1090... 

P. Herczegh, M. Zsdby, L. Szil gyi, Z. Dinya, and R. Bogndr, High diastereoselectian in the intramolecular Diels-Alder reaction of sugar-based 1,7(BZ),9-decatrienes, Tetrahedron 45 5995 (1989). 

The higher homologue of 3-sulfolene, 2,7-dihydrothiepin-l,1-dioxide could be similarly metallated at low temperatures. Reaction with reactive electrophiles followed by extrusion of sulfur dioxide led [549] to the corresponding hexatriene derivatives, as in the stereoselective synthesis of (Z,E)-l,3,5-decatriene (considered as an undecatriene in the publication) shown here. 

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