1,3,5-Cycloheptatrienes 1.3- cycloheptadienes

Compounds in which the RsSn group is attached to a 2,4-dienyl group, such as cyclopentadiene, cycloheptadiene, cycloheptatriene, and cyclononatetraene, whose formulas are shown, are fluxional. 

The complex functions as the most suitable source of the tricarbonylruthe-nium unit in syntheses of tricarbonyl(7-diene)ruthenium complexes. Derivatives of 1,3-cyclohexadiene, 1,3-cycloheptadiene, cycloheptatriene, cyclooc-tatetraene, 2,4,6-cycloheptatrien-l-one, bicyclo[3.2. l]octa-2,6-diene, bicyclo-[3.2. l]octa-2,4-diene, and butadiene have been prepared by displacement of 1,5-cyclooctadiene. 

The electrochemical reduction of cycloheptatriene (CHT) in liquid ammonia takes place at about —2.5 V vs SCE and forms the radical anion of CHT. The radical anion is stable in ammonia on the voltammetric time scale but decays slowly by disproportionation and coupling reaction pathways to give respectively 1,3- and 1,4-cycloheptadienes (total yield 34-39%) and C14H18 (in yields of 55-58%) isomers which incorporate the bitropyl carbon skeleta20. 

The l-oxa-2,4,5-cycloheptatrienes 602 and 603 were postulated to be intermediates in the rearrangement of certain (ethynylfuryl)oxiranes to furo[3,4-b]furans [251]. The replacement of the methylene groups of 1,2-cycloheptadiene (465) by SiMe2 groups and the introduction of substituents at the allene moiety allowed the preparation of isolable seven-membered ring allenes. Thus, Barton et ah [177] obtained 604 and Ando et al. [178] 605. A few reactions of these systems have also been studied [177, 252]. Both groups [178, 253] synthesized the [4.4]betweenallene 606 and determined its structure by X-ray diffraction. 

C7H7 = tropylium C7II8 = cycloheptatriene C7II9 = cycloheptadienium C7H10 = cycloheptadiene... 

Cyclodecyl cation hydride bridge, 147 1,4-Cycloheptadiene, 170, 171 Cycloheptatriene, 281 Cycloheptatrienes rearrangements, 290 Cycloheptatrienylidene, 275 interaction diagram, 276... 

The diamagnetic susceptibility measurements are consistent with the NMR properties of cycloheptatrienes. Pikulik and Childs compared the H NMR chemical shifts of the C(7) proton of 7-substituted cycloheptatrienes and the corresponding 1,4-cycloheptadienes and showed that there was a considerable upfield shift of the resonance of the former protons... 

Cycloheptadiene complexes are useful synthetic building blocks in the preparation of complex organic and natural products. A variety of substituted cycloheptadiene complexes can be prepared via catalytic hydrogenation of the respective cycloheptatriene-Fe(CO)3 complex. Subsequent oxidation liberates the iron carbonyl moiety affording the uncomplexed substituted cycloheptadiene complex (Scheme 34). 

Cyclobutenyhnethyllithium, 494 Cyclodecyl acetate, 343 Cyclodehydration, 435 Cyclodextrins, 129 3,5-Cycloheptadiene-l-ol, 340 Cycloheptanes, 273, 328-329 Cycloheptatriene, 338 Cycloheptenones, 68, 69... 

The reaction of 1,3-cyclohexadiene with FeCls in an ether solution of iso-C3H7MgBr produces the complex with mixed ligands (l,3-C,jHn Fe-(CflH(,) (204). Similarly by irradiation of FeClg with a mixture of 1,3,5-cycloheptatriene and 1,3-cycloheptadiene in the presence of iso-CsH7MgBr, Fischer and Muller (206) have prepared the air-sensitive and thermally unstable complex with mixed ligands (1,3,5-C7Hh)(1,3-C7Hio)Fe. Fe(CO)5 reacts with cycloheptatriene to produce not only... 

With [(i r(PhC02Me)(C0)3], 1,3,5-cycloheptatriene gives 1,3-cycloheptadiene and cycloheptene in successive steps. ... 

Cp2TiCl2 reacts with MgCIPr1 in the presence of cycloheptatriene to give 73-cycloheptadienyltitanium isomers (Scheme 491), which undergo in situ addition to aldehydes to produce a mixture of 1,3- and 1,4-cycloheptadienyl alkyl (aryl) carbinols. The reaction opens a simple way to functionalized 1,4-cycloheptadienes, some of which are closely related to biologically active compounds.1159... 

Diene)Mn(CO)3 anions are stable in solution, and have been characterized by infrared and NMR spectroscopy. However, exposure of the anion solution to oxygen results in decomposition to give the free ligand. Reduction of (crotyl)Mn(CO)4 (62) gives the manganese-carbonyl transfer reagent ( -2-butene)Mn(CO)4. Reaction of 1,3-cycloheptadiene, 1,3-cyclooctadiene, 1,3,5-cycloheptatriene or 1,3,5,7-cyclooctatetraene... 

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