Phthalide sources

Bromobenzyl alcohol and its derivatives were converted to phthalides by the palladium catalysed insertion of carbon monoxide and intramolecular quenching of the formed acylpalladium complex. 2-Hydroxymethyl-1-bromonaphthaline, for example, gave the tricyclic product in excellent yield (3.34.). An interesting feature of the process is the use of molybdenum hexacarbonyl as carbon monoxide source. The reaction was also extended to isoindolones, phthalimides and dihydro-benzopyranones 42... 

In this article, we review the chemical structures and sources of the currently known naturally occurring phthalides of plant. Recent advances related to the biological activities of the extensively investigated natural phthalides are also described. As examples, we focus on the phthalide ingredients and medical uses of three commonly used phthalide-containing TCM herbs. 

PLANT Sources, chemical structures and classifications of natural phthalides Chemical Structure of Phthalide... 

Table I. Plant Sources of Naturally Occurring Phthalides...

Under mild conditions (1-4 bar CO, 25-60 °C), high yields of the desired produets were produced. Benzyl, allyl, aryl, and vinyl halides containing primary, secondary, or tertiary aleohol groups were readily converted to a variety of lactones, including phthalides and butenolides (Scheme 2.160a). Sinee then, 2-bromo benzyl aleohol has been tested as a substrate in various systems, such as carbonylation with a flow microreactor,[ C]-labelled compounds, and microwave-promoted with Mo(CO)g as a carbon monoxide source (Scheme 2.160b). Cobalt carbonyl as a cheaper catalyst was also applied in the intramolecular cyclization of aryl halides (Scheme 2.160c). ... 

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