Phosphine/palladium-catalyzed syntheses of alkylidene phthalans, 3-deoxyisoochracinic acid, isoochracinic acid, and isoochracinol.
In this study we used sequential catalysis-PPh(3)--catalyzed nucleophilic addition followed by Pd(0)-catalyzed Heck cyclization--to construct complex functionalized alkylidene phthalans rapidly, in high yields, and with good stereoselectivities (E/Z ratios of up to 1:22). The scope of this Michael-Heck reaction includes substrates bearing various substituents around the alkylidene phthalan backbone. Applying this efficient sequential catalysis, we accomplished concise total syntheses of 3-deoxyisoochacinic acid, isoochracinic acid, and isoochracinol.
Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Yi Chiao
YC
Fan
Ohyun
O
Kwon
D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry*; D010795:Phthalic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
C576089:3-deoxyisoochracinic acid; D001572:Benzofurans; D010720:Phosphines; D010795:Phthalic Acids; C576090:isoochracinic acid; C576091:isoochracinol; D010165:Palladium; C044646:phosphine