Cyclododecatriene catalyst

Alkynes are easily carboxylated by C02 and usually offer lactones or pyrones as products. However, in several cases carboxylic acids can also be obtained. For example, 2-butyne reacted with C02 in the presence of a [Ni(CDT)] (CDT = 1,5,9-cyclododecatriene) catalyst and /V,/V,/V, /V -tetramethyl-l,2-diamine (TMEDA) as base to yield 2-methylcrotonic acid.21 Similarly, the reaction of terminal alkynes was catalyzed by Ni(COD) in a highly regio- and chemoselective manner in the presence of DBU as base affording E-acrylic acids in >85% yield (Scheme 6.13).84... 

Dodecanedioic Acid. Dodecanedioic acid (DDDA) is produced commercially by Du Pont ia Victoria, Texas, and by Chemische Werke Hbls ia Germany. The starting material is butadiene which is converted to cyclododecatriene usiag a nickel catalyst. Hydrogenation of the triene gives cyclododecane, which is air oxidized to give cyclododecanone and cyclododecanol. Oxidation of this mixture with nitric acid gives dodecanedioic acid (71). 

Conjugated dienes can be dimerized or trimerized at their 1,4 positions (formally, [4 4- 4] and [4 4-4 4-4] cycloadditions) by treatment with certain complexes or other transition metal compounds. " Thus butadiene gives 1,5-cyclooctadiene and 1,5,9-cyclododecatriene. " 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-alkene complexes. " ... 

WiESSMEiER, G., Honigke, D., Heterogeneously catalyzed gas-phase hydrogenation of cis,trans,trans-1,5,9-cyclododecatriene on palladium catalysts having regular pore systems,... 

Among transition metal complexes used as catalysts for reactions of the above-mentioned types b and c, the most versatile are nickel complexes. The characteristic reactions of butadiene catalyzed by nickel complexes are cyclizations. Formations of 1,5-cyclooctadiene (COD) (1) and 1,5,9-cyclododecatriene (CDT) (2) are typical reactions (2-9). In addition, other cyclic compounds (3-6) shown below are formed by nickel catalysts. Considerable selectivity to form one of these cyclic oligomers as a main product by modification of the catalytic species with different phosphine or phosphite as ligands has been observed (3, 4). 

A m-RuCl2(CO)2(PPh3)2 complex, which catalyzes hydrogenation of dienes and monoenes, becomes useful in the presence of added phosphine for selective hydrogenation of 1,5,9-cyclododecatriene to cyclododecene the catalyst is a HRuCl(CO)2(PPh3)2 hydride that operates via steps analogous to those of reactions (9)-(11) (144, 145). 

Butadiene when trimerised over Ziegler-Natta catalyst to yields 1, 5, 9-cyclododecatriene. Hydrogenation form cyclododecane which yields dodecyl lactam. 

In Tables 2.3-1 and 2.3-2 the products formed by Ti- and Ni-catalysts are compared with those formed by Cr catalysts. Ni- and Ti-catalysts show an opposite behavior in the fff/ffc-isomer distribution of 1,5,9-cyclododecatrienes and in 2 1- vs. 

Homogeneous nickel complexes proved to be versatile catalysts in dimerization and trimerization of dienes to yield different oligomeric products.46-55 Depending on the actual catalyst structure, nickel catalyzes the dimerization of 1,3-butadiene to yield isomeric octatrienes, and the cyclodimerization and cyclotrimerization to give 1,5-cyclooctadiene and all-trans-l,5,9-cyclododecatriene, respectively46 56 [Eq. (13.13)]. Ziegler-type complexes may be used to form cis,trans,trans-1,5,9-cyclododecatriene37,57 58 [Eq. (13.14)], which is an industrial intermediate ... 

The trimerization to produce cis,trans,trans- 1,5,9-cyclododecatriene has also been practiced commercially using a Ziegler-Natta catalyst... 

The titanium trichloride-diethylaluminum chloride catalyst converted butadiene to the cis-, trans,-trans-cyclododecatriene. Professor Wilke and co-workers found that the particular structure is influenced by coordination during cyclization between the transition metal and the growing diene molecules. Analysis of the influence of the ionicity of the catalyst shows effects on the oxidation and reduction of the alkyls and on the steric control in the polymerization. The lower valence of titanium is oxidized by one butadiene molecule to produce only a cis-butadienyl-titanium. Then the cationic chain propagation adds two trans-butadienyl units until the stereochemistry of the cis, trans, trans structure facilitates coupling on the dialkyl of the titanium and regeneration of the reduced state of titanium (Equation 14). 

Twelve-membered rings have been obtained using coordination catalysts. The trans,trans,cis-cyclododecatriene has been prepared with a tetrabutyl titanate—diethylaluminum chloride catalyst (48,49) and with a chromium-based system (50). The trans,trans,trans- somer has been prepared with a nickel system. 

The starting point of this development was the discovery by Wilke (18) of the synthesis of cyclododecatriene-1,5,9 from butadiene using typical organometallic mixed catalysts. 

Several cyclic oligomers 1-5 are prepared from butadiene using transition metal catalysts. The preparation of 1,5-cyclooctadiene (3 1,5-COD) by a catalyst prepared from Ni(CO)4 and phosphine is the first report on cyclooligomerzation of butadiene [1], However, the activity of this catalyst is low due to strong coordination of CO. Catalyst prepared from TiCU and EtjAl has higher catalytic activity for the formation of 1,5-COD and 1,5,9-cyclododecatriene (1,5,9-CDT 4). Also Ni(0) catalysts are active for the preparation of COD and CDT. In addition to COD and CDT, the cyclic... 

Nickel-triarylphosphite complexes catalyze the dimerisation of butadiene to cyclooctadiene. Cyclododecatriene is an unwanted by-product, which results from trimerization catalyzed by the same catalyst. Table 3.2 shows the product yields using various ligand-metal complexes (the remainder in each case is a tarry polymeric material). 

The reduction of nickel(II) in the presence of butadiene as the only available ligand (i.e., naked-nickel3) (69) produces a catalyst which is able to trimerize butadiene to a mixture of all-trans- trans,trans,cis- and trans,cis,cis-i, 5,9-cyclododecatriene in which the all-trans form predominates. 

CDT Polymerization. Following the general polymerization procedure described above, 1,5,9-cyclododecatriene was polymerized using 100 ml. of 1.57M solution of monomer in benzene and initiated by 2.0 ml. each of the catalyst Components A and B. The reaction was terminated after 30 minutes, and the product was isolated, processed, and analyzed for the low molecular weight extractable macrocyclic fraction as before. 

The hydrogenation of 1,5,9-cyclododecatriene (1,5,9-CDT) to cyclododecadienes (CDD) and cyclododecene (CDE) proceeds much less selectively than in the case of 1,5-COD. This may be due to the fact that the three double bonds in 1,5,9-CDT cannot assist each other on adsorption to catalyst, as may be deduced from the inspection of its molecular model. Thus, it is expected that the difference in strength of adsorption or reactivity between 1,5,9-CDT and CDD or CDE would be considerably smaller than that between 1,5-COD and COE. Hanika et al. studied the hydrogenation of 1,5,9-... 

Interestingly a Ziegler Natta catalyst (Chapter 7) consisting of TiCU associated with an aluminium alkyl co-catalyst in a 1 1 molar ratio, polymerizes butadiene, but it is also able to afford cyclododecatriene provided that the TiCU/co-catalyst molar ratio is kept approximately to 0.1 instead of 1 [M. Rapoport and D. L. Sullivan, Can. Patent 1 055 052 (1979), to DuPont]. Although the mechanism is unclear, this is a good example of how delicate can be the modulation of a catalytic system for a selective synthesis. 

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