Bicyclo decanOl

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... 

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). 

Similarly, 10-(4-mcthylphenylsulfonyl)bicyclo[6.2.0]decanol undergoes ring expansion-contraction upon exposure to boron trifluoride or alumina yielding /erm-fused bieyclo[7.1.0]decan-2-one (10)63. 

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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