Disclosed are methods for rerouting radical cascade cyclizations by using alkenes as alkyne equivalents. The reaction sequence is initiated by a novel 1,2 stannyl shift which achieves chemo- and regioselectivity in the process. The radical hopping leads to the formation of the radical center necessary for the sequence of selective cyclizations and fragmentations to follow. In the last step of the cascade, the elimination of a rationally designed radical leaving group via -CC bond scission aromatizes the product without the need for external oxidant. The Bu.sub.3Sn moiety, which is installed during the reaction sequence, allows further functionalization of the product via facile reactions with electrophiles as well as Stille and Suzuki cross-coupling reactions. This selective radical transformation opens a new approach for the controlled transformation of enynes into extended polycyclic structures of tunable dimensions.

Disclosed are methods for rerouting radical cascade cyclizations by using alkenes as alkyne equivalents. The reaction sequence is initiated by a novel 1,2 stannyl shift which achieves chemo- and regioselectivity in the process. The radical hopping leads to the formation of the radical center necessary for the sequence of selective cyclizations and fragmentations to follow. In the last step of the cascade, the elimination of a rationally designed radical leaving group via -CC bond scission aromatizes the product without the need for external oxidant. The Bu.sub.3Sn moiety, which is installed during the reaction sequence, allows further functionalization of the product via facile reactions with electrophiles as well as Stille and Suzuki cross-coupling reactions. This selective radical transformation opens a new approach for the controlled transformation of enynes into extended polycyclic structures of tunable dimensions.

The present invention is a method for producing a fluorohydrocarbon represented by a structural formula (3) comprising bringing a secondary or tertiary ether compound represented by a structural formula (1) into contact with an acid fluoride represented by a structural formula (2) in a hydrocarbon-based solvent in the presence of a boron trifluoride complex. (In structural formulae (1) to (3), each of R.sup.1 and R.sup.2 represents an alkyl group having 1 to 3 carbon atoms, R.sup.3 represents a hydrogen atom, a methyl group, or an ethyl group, and each of R.sup.4 and R.sup.5 represents a methyl group or an ethyl group, provided that R.sup.1 and R.sup.2 are optionally bonded to each other to form a ring structure.)

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The present invention is a method for producing a fluorohydrocarbon represented by a structural formula (3) comprising bringing a secondary or tertiary ether compound represented by a structural formula (1) into contact with an acid fluoride represented by a structural formula (2) in a hydrocarbon-based solvent in the presence of a boron trifluoride complex. (In structural formulae (1) to (3), each of R.sup.1 and R.sup.2 represents an alkyl group having 1 to 3 carbon atoms, R.sup.3 represents a hydrogen atom, a methyl group, or an ethyl group, and each of R.sup.4 and R.sup.5 represents a methyl group or an ethyl group, provided that R.sup.1 and R.sup.2 are optionally bonded to each other to form a ring structure.)

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The present invention relates to a method for the chemical conversion of an unsaturated fatty acid, particularly a carbon chain extension reaction. According to the present invention, a method for extending the length of a carbon chain in an unsaturated fatty acid by two carbon atoms is provided, said method comprising a step of heating a malonic acid ester derivative of an unsaturated fatty acid to reflux in a lower fatty acid solution in the presence of an antioxidative agent. It is preferred that the unsaturated fatty acid is an unsaturated fatty acid having 16 to 24 carbon atoms. It is preferred that the unsaturated fatty acid is selected from the group consisting of linoleic acid, linolenic acid, arachidonic acid, stearidonic acid, icosatetraenoic acid, icosapentaenoic acid, tetracosahexaenoic acid and docosahexaenoic acid. According to the method of the present invention, a carbon chain extension reaction can be completed within a shorter time.

The present invention relates to a method for the chemical conversion of an unsaturated fatty acid, particularly a carbon chain extension reaction. According to the present invention, a method for extending the length of a carbon chain in an unsaturated fatty acid by two carbon atoms is provided, said method comprising a step of heating a malonic acid ester derivative of an unsaturated fatty acid to reflux in a lower fatty acid solution in the presence of an antioxidative agent. It is preferred that the unsaturated fatty acid is an unsaturated fatty acid having 16 to 24 carbon atoms. It is preferred that the unsaturated fatty acid is selected from the group consisting of linoleic acid, linolenic acid, arachidonic acid, stearidonic acid, icosatetraenoic acid, icosapentaenoic acid, tetracosahexaenoic acid and docosahexaenoic acid. According to the method of the present invention, a carbon chain extension reaction can be completed within a shorter time.

The disclosure is directed to: (a) phosphacycle ligands; (b) catalyst compositions comprising phosphacycle ligands; and (c) methods of using such phosphacycle ligands and catalyst compositions in bond forming reactions.

The disclosure is directed to: (a) phosphacycle ligands; (b) catalyst compositions comprising phosphacycle ligands; and (c) methods of using such phosphacycle ligands and catalyst compositions in bond forming reactions.

The process is provided for forming the reaction product comprising the homologue mixture of I(CF.sub.2).sub.nI, wherein n is 3 to 7, which may contain at least one of the contaminants ICF.sub.2I and I(CF.sub.2).sub.2I, by the steps comprising (a) reacting iodine with hexafluoropropylene oxide at a temperature of 150 C. to 210 C. in a reactor, the amount of said hexafluoro-propylene oxide being a portion of the total amount of hexafluoropropylene oxide to be reacted with said iodine, thereby forming a reaction product containing gaseous perfluoroacetyl fluoride as a reaction by-product, (b) cooling said reaction product to become liquid except for said gaseous perfluoroacetyl fluoride, (c) venting said perfluoroacetyl fluoride from said reactor, and (d) repeating said steps (a), (b), and (c) until said total amount of said HFPO is reacted with said iodine.

The process is provided for forming the reaction product comprising the homologue mixture of I(CF.sub.2).sub.nI, wherein n is 3 to 7, which may contain at least one of the contaminants ICF.sub.2I and I(CF.sub.2).sub.2I, by the steps comprising (a) reacting iodine with hexafluoropropylene oxide at a temperature of 150 C. to 210 C. in a reactor, the amount of said hexafluoro-propylene oxide being a portion of the total amount of hexafluoropropylene oxide to be reacted with said iodine, thereby forming a reaction product containing gaseous perfluoroacetyl fluoride as a reaction by-product, (b) cooling said reaction product to become liquid except for said gaseous perfluoroacetyl fluoride, (c) venting said perfluoroacetyl fluoride from said reactor, and (d) repeating said steps (a), (b), and (c) until said total amount of said HFPO is reacted with said iodine.