modification of the classical Julia olefination. The replacement of the phenyl sulfones with heteroaryl sulfones greatly alters the reaction pathway. The most popular example is the benzothiazole sulfone. The reaction of the benzothiazole sulfone (1) with lithium diisopropylamide (LDA) gives a metallated benzothiazolyl sulfone, which reacts quickly with aldehydes (or ketones) to give an alkoxide intermediate (2). Unlike the phenyl sulfones, this alkoxide intermediate (2) is more reactive and will undergo a Smiles rearrangement to give the sulfinate salt (4). The sulfinate salt (4) will spontaneously eliminate sulfur dioxide and lithium benzothiazolone (5) producing the desired alkene (6). Since the benzothiazole variation of the Julia olefination does not involve equilibrating intermediates, the stereochemical outcome is a result of the stereochemistry of the initial carbonyl addition. As a result, this reaction often generates a mixture of alkene stereoisomers. Julia–Kocienski olefination The Julia–Kocienski Olefination, a further refinement of the Modified Julia olefination, offers very good E-selectivity. In the Julia–Kocienski olefination the alkylating agent is a tetrazole. It proceeds with the same mechanism as the benzothiazole sulfone above. The high E-selectivity of the Julia–Kocienski olefination is the result of kinetically controlled diastereoselective addition of metalated 1-phenyl-1H-tetrazol-5-yl (PT) sulfones to nonconjugated aldehydes. This yields anti-β-alkoxysulfones which stereospecifically decompose to the E-alkenes. In one adaptation, with t-butyltetrazoylmethyl sulfone the reaction conditions are either sodium bis(trimethylsilyl)amide at −70 °C in tetrahydrofuran or caesium carbonate at +70 °C. This reaction is named after Philip J. Kocienski for his modification to the Julia olefination. Synthetic Applications The Julia or modified Julia olefination reaction is a powerful and versatile synthetic transformation, widely utilized in the construction of complex natural products with excellent control of geometrical isomerism. Pterostilbene Pterostilbene is a stilbenoid chemically related to resveratrol. It belongs to the group of phytoalexins, agents produced by plants to fight infections. Pterostilbene is a naturally occurring dimethyl ether analog of resveratrol. It is believed that the compound also has anti-diabetic properties, but so far very little has been studied on this issue. Compared to the Wittig, Wittig-Horner, Perkin, or transition-metal-catalyzed reactions to synthesize pterostilebene, the Julia olefination offers a simple, economical alternative method for preparation of pterostilbene. Resveratrol One adaptation of the Julia-Kocienski olefination gives the synthesis of the stilbenoid resveratrol, a natural compound found in common foods like grapes, wines and nuts. Resveratrol is a biologically important stilbenoid which has been suggested to have many health benefits. The Julia-Kocienski olefination