3.6,9-Dodecatrienal

A solution of 45 mmols of 1-bromo-3,7,11-trlmethyl-2,6,10-dodecatriene (obtained from synthetic farnesol, commercially available and containing four isomers) in 10 ml of benzene was added dropwise at 0 to a stirred solution of 45 mmols of piperonylpiperazine in 60 ml of benzene containing 5 g of triethyiamine. The mixture was stirred for 2 hours and then the precipitated triethyiammonium bromide was fiitered off. The benzene soiution was washed first with water and then with K2CO3 soiution and finaliy dried (K2CO3). Removal of ben-... 

Dodecatrien-1-ol, 3,7,11-trimethyl-, (E,E)-] (Note 1) and 40 ml. of dry pyridine (Note 2) is prepared in a stoppered 250-ml. Erlenmeyer flask, and 40 ml. of acetic anhydride is added in four portions over a 15-minute period. The mixture is stirred well and allowed to stand for 6 hours and then poured onto 250 g. of ice. Water is added (400 ml.), and the mixture is extracted with five 100-ml. portions of petroleum ether (b.p. 60-68°). The organic extracts are combined and washed in succession with two 50-mi. portions each of water, 5% aqueous sulfuric acid, and saturated aqueous sodium bicarbonate. Anhydrous magnesium sulfate (ca. 50 g.) is used to dry the petroleum ether solution, which is then concentrated on a rotary evaporator to provide 28-29 g. (94-98%) of famesyl acetate as a colorless oil (Note 3). 

The extensive study of Craig and coworkers [116] on the intramolecular Diels-Alder reactions of E- and Z-sulphonyl-substituted deca-, undeca- and dodecatrienes 120 (Figure 2.13) has opened a short route to trans- and cis-bridgehead hydrindanes and decalines and has given new insights into the role of dienophile substitution and geometry in determining the stereochemical outcome of these intramolecular cycloadditions. 

One other reaction deserves mention. From bis(cyclooctadiene)nickel and butadiene (31), and in the presence of an isocyanide (RNC, R = cyclohexyl, phenyl, tcrt-butyl) two organic oligomeric products are obtained, 1 -acylimino-11 -vinyl-3,7-cycloundecadiene and 1 -acylimino-3,7,11 -cyclo-dodecatriene. In each, one isocyanide has been incorporated. An analogous reaction with carbon monoxide had been reported earlier. The proposed mechanism of these reactions, via a bis-7r-allyl complex of nickel, is probably related to the mechanism described for allylpalladium complexes above. 

Fig. 7. Selected geometric parameters (A) of the optimized rotational transition-state structure for antilsynA-trans bis(syn),A-trans conversion via the n3-1sTn,V(C3),A-tr

Similar studies on the reactions of butadiene and bis(ir-allyl)palladium were carried out by Wilke and co-workers (4). Unlike the reactions with nickel complexes, no cyclization took place, and 1,6,10-dodecatriene... 

Murakami and co-workers have shown that phenyl- and vinyl-substituted vinylallenes react in a palladium-catalyzed intermolecular [4+ 4]-cycloaddition in the presence of a palladium complex to give the cyclooctadiene cycloadducts in moderate to good yields (Scheme 29).103 In a method reported by Lee and Lee, bicyclo[6.4.0]-dodecatrienes are prepared in good overall yields via a two-step, one-flask procedure that involves a serial palladium-catalyzed cross-coupling/[4 + 4]-cycloaddition followed by [4 + 2]-cycloaddition (Scheme 30). Overall, this two-step process impressively brings together five simple components to form relatively complex bicyclic products.1... 

The patent literature contains several references to the use of sulfoxide complexes, usually generated in situ, as catalyst precursors in oligomerization and polymerization reactions. Thus, a system based upon bis(acrylonitrile)nickel(0> with added Me2SO or EtgSO is an effective cyclotrimerization catalyst for the conversion of butadiene to cyclo-1,5,-9-dodecatriene (44). A similar system based on titanium has also been reported (407). Nickel(II) sulfoxide complexes, again generated in situ, have been patented as catalyst precursors for the dimerization of pro-pene (151) and the higher olefins (152) in the presence of added alkyl aluminum compounds. 

Another, and quite telling, example concerns the structure-specific elimination of olefins from acyclic trienes (Scheme 6). Bestmann and coworkers70 found that the El spectra of (8 ,10Z)-l,8,10-dodecatriene (23, R = H), (11 ,13Z)-1,11,13-pentadecatriene and some of their homologues display characteristic peaks at m/z 68, 82, 96 etc., corresponding to the formation of ionized alkadienes C5 Hs 12n 1L along with a neutral diene. The peaks... 

Nickel 2,6,10-dodecatrien -1,12-diyl, as catalyst for butadiene polymerization, 23 303 Nickel formate as nickel catalyst, 32 226-229 Nickel hydride... 

The procedure described is based on the selective reduction with diimide described by Ohno and Okamoto and by Nozaki and Noyori. It illustrates the generation of diimide from the air oxidation of hydrazine and the use of diimide for the selective reduction of the trans double bond in cis,trans,trans-, S,9-cyc o-dodecatriene, the product of trimerization of butadiene. ... 

BIS(t 6-CHLOROBENZENE)MOLYBDENUM, BIS(776-iV,Ar-DIMETHYLANILINE)MOLYBDENUM, AND (1-3 6-7 10-12-rj-2,6,10-DODECATRIENE-1,12-DIYL)NICKEL... 

The increased cooling efficiency of thin-walled reactors also has permitted the use of more volatile substrates in near molar quantities. (l-3 6-7 10-12-rj 2,6,10-Dodecatriene-l,12-diyl)nickel has been prepared in multiple gram quantities by cocondensation of nickel vapor and 1,3-butadiene. This method has provided a clean one-step route to this complex, which was first isolated and identified by Wilke et al.1 as an intermediate in the cyclotrimerization of 1,3-butadiene by nickel catalysts. 

T -2,6,10-dodecatriene-l,12-diyl)nickel is an air-sensitive compound with a melting point of 15-16° the literature value is 1°. Although the melting point of this product found by the present authors is considerably higher than reported in Reference 2 it was reproducible from run to run. However, the mass and NMR1 spectra accorded well with the literature and it seems possible that a variation of isomer distribution, as discussed in Reference 2, accounts for the difference. 

C15H24O, Mr 220.36, 20 0.962-0.980, 1.504-1.509, is a colorless to pale yellow liquid with powerful complex woody and amber odor. It does not occur in nature. It is prepared by monoepoxidation of l,5,9-trimethyl-l,5,9-dodecatriene with, e.g., peracids. 

In the presence of 1,3-butadiene, diamino octodienes and dodecatrienes are formed Amination of aromatic compounds has been mentioned above (Sect. 3.3.3) Sensitive substituted hydroxylamines may be reduced to the amines in oxylic acid using electro-generated titanium(III)... 

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