Allylation alkynes

Treatment of tethered alkyne-allyl halides with indium metal in halogenated solvents affords carbocyclic vinyl halides via a novel atom-transfer reaction. The reactions are operationally facile and proceed smoothly at room temperature even with sub-stoichiometric quantities of indium. Use of a halogenated solvent containing a different... 

However, this intriguing catalyst system is capable of performing a subsequent reductive amination in the same pot and under the same conditions if secondary amines are added and if an atmosphere of hydrogen is introduced. Therefore, alkyne allyl alcohols 200 are readily transformed in moderate to good yields into /J-amino ethyl alkylidene tetrahydrofurans 203... 

We can only note that alkene, alkyne, allyl, and related compounds of many types are known. Important ruthenium starting materials are RuC12(COD) and Ru(COD)(2-methylallyl)2, both of which are commercially available. 

Alkynes. Allyl Alcohols Addition to the unsoturoted bond 982,1038... 

This section deals mainly with the hydrostannation of alkenes, and further details can be found in the appropriate subsequent sections on, for example, stannyl radicals (Section 20.1.3), and stannacycloalkanes (Chapter 10). The hydrostannation of alkynes, allyl compounds, and allenes, is dealt with in Sections 8.1.1 and 10.1. which cover the vinyl-and allyl-tin compounds which are produced. 

Metallo-ene cychzations, intramolecular Pd(0), Ni(0), Rh(I), Zn(0) catalyzed alkene (or alkyne) allylations [62, 63, 64], have been recognized as a powerful tool in organic synthesis due to the synthetically useful functionalizations such as carbonylation or C-C coupling. The high regio- and stereoselectivities also al-... 

The reaction type (a) (L = OAc) in Scheme 15 takes place in the palladium-catalyzed reaction of the alkyne-allyl acetates 57 with acetic acid the trans-acetoxypalladation of alkyne leads to 59, and subsequent carbopalladation of alkene followed by deace-toxypalladation gives the five-membered heterocycles 2-alkenylidenelactones 58 (Scheme 20).101a... 

The ease of interaction of Ni(0) complexes with organic substrates has been shown to depend upon both the ligands on nickel and the solvent. The presence of a,a-bipyridyl with the Ni(0) complex and the alkyne led to the isolation of a nickelacyclopropene, an observation in accord with the recently proposed metallocyclic pathway for the Ni(0)-cata-lyzed trimerization of alkynes. Allylic and benzylic ethers and epoxides have been observed to undergo oxidative insertion of Ni(0) into their C-0 bonds with solvent (TMEDA > THE > Et O > CeHe) and ligand (EtsP > PhsP a,a-bipy > COD) effects consistent with an electron-transfer attack by Ni(0). With such sulfur heterocycles as dibenzothiophene, phenoxathiin, phenothiazine, and thian-threne, a 1 1 admixture of (COD)2Ni with a,a-bipyridyl gave as the principal product the desulfurized, ring-contracted cyclic product. 

Reaction of alkyne allyl alcohols tethered with lV-(/7-tolylsulfonamide) in the presence of a cationic gold(I) catalyst give 4-oxa-6-azatricyclo[3.3.0.0 ]octanes (Scheme 113). ... 

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