Bicyclo decanone

Die Gewinnung des 6-Isopropylazulens [73] erfolgte auf analoge Weise fiber cis-Bicyclo-(0,3,5)-decanon-(6). Mittels des gleichen Synthcsewegs gelangten F. Sorm und J. Pokorny (133) vom 3-Methyl-cyclopentanon-2-carbon-saureester iiber das 10-Methyl-(0,3,5)-bicyclo-decanon-(3) zum... 

Zur Darstellmig des 5-Isopropyl [69]- und des 5-sec. Butylazulens [70] cyclisierten F. Sorm und J. Hlavni Cka (132) y-(2-Carboxymethyl-cyclopentyl)-buttersaure zum Bicyclo-(0,3,5 )-decanon-( 5), setzten letz-teres mit Isopropyl-lithium, bzw. sek. Butyl-lithium zum entsprechenden 5-Alkyl-bicyclo-(0,3,5)-decanol-(5) um, das sie zu den genannten Azulenen [69], [70] (R Isopropyl, sek.-Butyl) dehydratisierten und dchy-drierten... 

Examples with butynyl side chains followed essentially the same course in each case the product bicyclo[5.3.0]decanones were formed as single diastereomers with trans ring junctions. 

Similar a,a -annulations were achieved from reaction of a, -unsaturated acid chlorides with cyclic ketone enamines which afforded bicydo[3.3.1]nonane-2,9-diones or bicyclo[4.3.1]decanones . In this reaction, W-acylation of the enamine 109 occurs as the first step giving 110, followed by a [3,3] sigmatropic rearrangement to a ketene intermediate (111). Ketene 111 subsequently cyclized via 112 to a bicyclic immonium salt (113) which after hydrolysis gave the corresponding dione 114 , If there is an axially oriented electrophilic substituent at C-4 of the enamine (for example, R = COPh) the enolate anion 115 may cyclize to an adamantane derivative 116 (equation 20). 

A sequential alkoxyl radical fragmentation-transannular radical cyclisation has been used in a new approach to the bicyclo-[5.3.0]decanone ring system,irradiation of the 8-decanol (125) in the presence of iodosylbenzene diacetate and iodine, for example, gave the substituted hydroazulenone (126) via the mono-cyclic radical (127). 

Bicyclo[5,3,0]decanones (perhydroazulenones), preferentiaUy made from natural precursors (52CRV127, p. 163 59MI2, p. 302), are versatile intermediates in azulene s)mtheses, the final steps again consisting in dehydrogenation. Thus, semisynthetic ketodiol 17 (made from... 

Nine- and Ten-membered Rings.—Reduction of 1-bromo-cw-cyclononene and either l-bromo-trans,ds- or l-bromo-ds,cis-cyclonona-l,5-diene with sodium in liquid ammonia gave ds-cyclononene and cis,ds-cyclonona-1,5-diene, respectively." Thermolysis of bicyclo[7,l,0]deca-l,7-diene and bicyclo[8,l,0]undeca-1,8-diene gives 3-methylene-cis,ds-cyclonona-l,4-diene and a mixture of 3-methylene-ds,ds-cyclo-deca-1,4-diene and 10-methylenebicyclo[5,3,0]dec-8-ene, respectively. Cyclo-nonanone tosylhydrazone gives ds-cyclononene exclusively when treated with methyl or n-butyl lithium, whereas both cis- and trans-cyclodecenes are obtained from cyclo-decanone tosylhydrazone. The cis.trans olefin ratio in this case is solvent dependent probably, because of the effect of solvent on the tosylhydrazone conformation." ... 

A series of unsubstituted and 3-methyl-substituted bicyclo[x,y,0]alkanes (x = 9,10 y = 3,4) have been prepared from readily available precursors (e,g. cyclodo-decanone). Bicyclic analogues of exaltone and muscone were obtained in this work. 

An interaction of the intermediate carbon-centered radical (A) with a neighboring carbon-carbon bond in this ring expansion leads to a transannular radical cyclization the treatment of the unsaturated decanols with (diacetoxyiodo) benzene-iodine followed by irradiation underwent fragmentation of intermediate allyloxy radicals (A) to give the bicyclo(5.3.0]decanones (40-78%) and to give the 7,5,5-tricycKc compound (81%) by way of a Billiard reaction, as outlined in Scheme 687 ... 

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