Platinum-catalysed reactions allylation

The formation of D-glucaric acid by platinum-catalysed oxidation of D-gluconic acid has been noted in the previous section. Mono- and per-allyl ether derivatives of xylaric and galactaric acids have been prepared by treating the aldaric acid with allyl alcohol in the presence of an appropriate acid catalyst. Diallyl 3-0-allyl-2,4-0-methylenexylarate was obtained in good yield when 2,4-0-methylenexylaric acid reacted with allyl bromide in the presence of alkali. The reaction of 2,3,4-tri-O-acetylxylaryl dichloride with diazomethane has been mentioned in Chapter 7. 

Platinum(II) chloride-catalysed reaction of allenes R R C=C=CHR with N-protected indoles (In) in THF with added MeOH proceeds at 70 C over 20 h and affords products of geminal bisindolylation, that is, R R CH-CH2C(3-In)2R. By contrast, gold(I) complexes catalyse monoindolylation, giving rise to allyl indoles... 

A cascade reaction for the construction of spirobenzo[/t]chromanone and spiropyranone derivatives was achieved by a platinum-catalysed tandem cyclization/[l,2]-alkyl migra-tion/allyl shift of epoxy alkynyl allyl ethers followed an aromatic cyclization reaction (Scheme 142). ... 

---