A simple and efficient procedure has been developed for the synthesis of organostannane compounds by one-pot reaction of stannane halides, magnesium turnings and organic halides in the presence of 1,2-dibromoethane under ultrasound irradiation.
A highly stereoselective synthesis of the side chain enantiomers of brassinolide and dolicholide through an aldol reaction of 2-(4-methoxy benzyloxyl) propionylaldehyde (5) with the anion of 1-(tert-butyldimethylsiloxy)-3-methyl-2-butanone (6) is described.
First total synthesis of saurufuran B 1, a furanoditerpene, from （E, E）-farnesol 2 and citraconic anhydride 3 through thirteen steps is described. Our work involves two key steps： （1） High regioselective alkylation of 2-（tert-butyldimethylsiloxy）-4-methylfuran 6 with aUylic iodides 5 in the presence of silver wifluoroacetate and （2） Conversion of substituted 7-1actone 7 into furan derivative 8.
An efficient total synthesis of 6-oxodendrolasinolide 1, a new farnesane-based homosesquiterpene lactone, starting from geraniol 2 through twelve steps is described. Our work involved two key steps： （1） regioselective alkylation of the anion of vinyldithian 5 with allylic chloride 31, （2） Corey＇s oxidative lactionization method2.
Dehydrogenation of 9-hydroxy decalinic enones and analogs with DDQ resulted in a formal dienone-phenol type rearrangement via B-ring cleavage, while the corresponding dienone acetates underwent base-catalyzed formal dienone-phenol type rearrangement analogously.
