Cyclododecanone CYCLODODECENE

To a 3QQ-mL, round-bottomed flask fitted with a water separator, (Note 1) which contains 15 g of Linde 4A molecular sieve l/16-1nch pellets and Is filled with toluene, are added 7.3 g (0.04 mol) of cyclododecanone, 11.4 g (0.16 mol) of pyrrolidine, 100 mL of toluene, and 0.57 g (0.004 mol) of boron trifluoride etherate. The solution is heated under reflux for 20 hr. The water separator is replaced by a distillation head, and about 90 mL of the toluene is removed by distillation at atmospheric pressure. The residue containing l-(N-pyrrolidino)-l-cyclododecene (1) is used in the next step without further purification (Note 2). 

Cyclododecene may be prepared from 1,5,9-cyclododecatriene by the catalytic reduction with Raney nickel and hydrogen diluted with nitrogen, with nickel sulfide on alumina, with cobalt, iron, or nickel in the presence of thiophene, with palladium on charcoal, with palladimn chloride in the presence of water, with palladium on barium sulfate, with cobalt acetate in the presence of cobalt carbonyl, and with cobalt carbonyl and tri- -butyl phosphine. It may also be obtained from the triene by reduction with lithium and ethylamine, by disproportionation, - by epoxidation followed by isomerization to a ketone and WoliT-Kishner reduction, and from cyclododecanone by the reaction of its hydrazone with sodium hydride. ... 

Sumimoto introduced a new sebacic acid process including several catalytic hydrogenation reactions.342 The synthesis starts with naphthalene, which is first partially hydrogenated to tetralin over cobalt oxide or molybdenum oxide, then to decalin over ruthenium or iridium on carbon. The selectivity to cw-decalin is better than 90%. In a later phase of the synthesis 5-cyclododecen-l-one is hydrogenated over Raney nickel to obtain a mixture of cyclododecanone and cyclodode-canol in a combined yield of 90%. The selectivity of this step is not crucial since subsequent oxidation of either compound leads to the endproduct sebacic acid. 

Cyclic ketones are suitable starting material for the preparation of corresponding oximes and dicarbonic acids, which are key intermediates for the production of various types of nylons. Recently, BASF announced [176] the development of a new process for cyclododecanone production via the ketonization of cyclododecene (entry 4, Table 7.9), for which commercialization is expected in 2009. 

Cyclododecadiyne, 356 Cyclododecane oxide, cis- and trans-, 247 Cyclododecanone, 212, 213, 327, 350, 420 rrans-Cyclododecene, 269 trans-2-Cyclododecenol, 247... 

Chromyl chloride can also produce ketones, but a common side reaction is formation of an a-chloro ketone, as in the conversion of cyclododecene to a-chlorocyclododecanone (401) in 79% yield. In a subsequent reaction, the chloride moiety in 401 was reduced to give cyclododecanone in 95% yield with zinc and acetic acid. Chromyl chloride also reacts with alkenes to give a trans-chlorohydrin rather than a carbonyl compound (see sec. 2.10.C for the preparation of chlorohydrins), as in the conversion of cyclohexene to tran5-2-chlorocyclohexanol. 5 It is interesting that in this particular case (the temperature was maintained at -78°C in dichloromethane), the cis-chlorohydrin was formed. ... 

Reductive deoxygenation of cyclododecanyl pivalate by photolysis in the presence of trichlorosilane gave a mixture of cyclododecane and cyclododecanyl,2,2-dimethyl-propyl ether.The disulphonimide (350) reacts with DMSO and sodium bicarbonate to give a mixture of cyclododecenes (88 %) together with cyclododecanone (5... 

Cyclododecane Cyclododecanol Cyclododecanone 1,5,9-Cyclododecatriene c/s-Cyclododecene f/3/i5-Cyclododecene c/s-9-Cycloheptadecen-1-one 1,3-Cycloheptadiene Cycloheptanamine... 

Dodecanedioic acid is prepared from cyclododecene (obtained from butadiene) by methods which are entirely analogous to those used to prepare adipic acid from benzene (section 10.2.2(a)). The cyclododecene is reduced to cyclododecane, which is oxidized firstly to a mixture of cyclododecanol and cyclododecanone and then to dodecanedioic acid. Dodecanedioic acid is a colourless crystalline solid, m.p. 129°C. 

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