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An asymmetric total synthesis of the proposed structure of (16Z,20E)-eushearilide, a novel 24-membered macrolide, was achieved via an enantioselective aldol reaction and 2-methyl-6-nitrobenzoic anhydride-mediated macrolactonization. The obtained synthetic compounds were not identical to the natural product. The newly proposed most likely structure of eushearilide, (±)-(16E,20E)-eushearilide, was determined on the basis of detailed NMR analysis, and (3R,16E,20E,23R)-(−)-eushearilide was successfully synthesized. A comparison of the optical rotation of (3R,16E,20E,23R)-(−)-eushearilide with that of the natural product confirmed that the true structure of naturally occurring eushearilide is the (3S,16E,20E,23S)-(+)-form.

A general method for the kinetic resolution of racemic α-arylalkanoic acids with achiral alcohols is described. It was determined that bis(9-phenanthryl)methanol is a suitable nucleophile which reacts with the intermediary mixed anhydrides generated from aromatic anhydrides with α-arylpropanoic acids or β-substituted-α-arylpropanoic acids in the presence of (+)-benzotetramisole to produce the corresponding optically active esters with high ee’s under very mild conditions.

The stereoselective total syntheses of botcinic acid, botcinic acid methyl ester, 3-O-acetylbotcinic acid methyl ester, botcineric acid, and botcinin E were achieved. The structures of these compounds have been unequivocally determined through their total synthesis, and they are identified with the revised structures of botcinolide, 4-O-methylbotcinolide, 3-O-acetyl-5-O-methylbotcinolide, homobotcinolide, and 2-epibotcinolide, respectively.

A variety of optically active carboxylic esters are produced by the kinetic resolution of racemic secondary benzylic alcohols using free carboxylic acids with benzoic anhydride and tetramisole derivatives. 4-Methoxybenzoic anhydride (PMBA) is the best reagent to use in producing the corresponding esters in high ee when the reaction is catalyzed by (+)-benzotetramisole (BTM); by contrast, when non-substituted benzoic anhydride is used as a coupling reagent, the resulting optically active alcohols are obtained with high selectivities. This protocol directly produces chiral carboxylic esters from free carboxylic acids and racemic secondary alcohols by utilizing the trans-acylation process to generate mixed anhydrides from acid components and benzoic anhydride derivatives under the influence of chiral catalysts.

A short-step route for the preparation of droloxifene has been established via the novel three-component coupling reaction among 3-pivaloyloxybenzaldehyde, cinnamyltrimethylsilane, and β-chlorophenetole, the successive installation of the side-chain part, and the base-induced migration of the double bond. The present synthesis of tetra-substituted ethylene moieties is a widely applicable strategy for producing a variety of SERMs (selective estrogen receptor modulators) and SARMs (selective androgen receptor modulators), such as tamoxifen, raloxifene, and other compounds that can lead to new drugs.

A method for the synthesis of octalactin B is established via a new and quite effective mixed-anhydride lactonization for the synthesis of an eight-membered ring moiety using 2-methyl-6-nitrobenzoic anhydride with DMAP. Both an optically active linear precursor of the lactone and a side chain of octalactins are prepared by the enantioselective aldol reaction of ketene silyl acetals with aldehydes.

The Friedel–Crafts alkylation reaction of various aromatic compounds with benzyl or allyl silyl ethers is effectively promoted under mild reaction conditions using Lewis acid catalysts. A mixture of the desired phenyltolylmethanes is obtained in 80% yield from toluene with benzyl dimethylsilyl or trimethylsilyl ether at 50°C in the presence of a catalytic amount of Cl 2 Si(OTf) 2 or Hf(OTf) 4 .

The three-component coupling reaction among aromatic aldehydes, allyltrimethylsilane and aromatic nucleophiles is efficiently performed by the promotion of HfCl 4 . A similar reaction occurs using allyltributyltin as the first nucleophile to aromatic aldehydes with a catalytic amount of Cl 2 Si(OTf) 2 generated in situ from SiCl 4 and AgOTf.

A novel [1,3] sigmatropic rearrangement of ketene silyl acetals derived from benzyl α-substituted propanoates is developed. The reaction of ketene silyl acetal derived from optically active 1-phenylethyl 2-methylpropanoate mainly proceeds with the retention of chirality at the benzyl position to give the corresponding optically active silyl ester under thermodynamic conditions.

A new method for the synthesis of optically active anti-vic-hydroxymethyl units that correspond to anti-aldol derivatives is developed by way of successive enantioselective aldol and diastereoselective desulfurization reactions.

The anti-tumor agent, tamoxifen, is easily synthesized by the successive allylation of benzaldehyde and the Friedel–Crafts alkylation reaction of anisole with the intermediary homoallyl silyl ethers, followed by the migration of the double bond to form the desired tetra-substituted ethylenes. Several derivatives of tamoxifen are also produced according to a similar synthetic strategy.

Of the 16 possible modes of the oxidation-6π-electrocylization-Diels–Alder reaction cascade for an epoxyquinone, and eight for a 2-alkenyl-3-hydroxymethyl-2-cyclohexen-1-one, only the endo - anti (epoxide) -anti (Me)-hetero and endo - anti (Me)-hetero are respectively observed, while both the endo - anti (epoxide) -anti (Me)-hetero and exo - anti (epoxide) -anti (Me)-homo reaction modes occur with epoxy-4-hydroxycyclohexenones owing to a hydrogen-bonding interaction.