The Julia Reaction

Direct Olefination of Alcohols with Sulfones by Using Heterogeneous Platinum Catalysts

“…Disubstituted benzyl alcohol, 3,4-dimethoxybenzyl alcohol (entry 9), was successfully transformed to 1,2-dimethoxy-4vinylbenzene in 91 %y ield. Naphthyl alcohols (1-and 2-naphthylmethanol) were convertedt og ive the correspondingv inyl naphthalene products in high yields (entries 11 and 10, respectively).H eteroaromatic alcohols with furanyl,t hienyl, pyridinyl, and benzo [1,3]dioxonyl groups were also tolerated, and the corresponding olefins were obtained in 78, 75, 84, and 89 % yield, respectively (entries 12-15). Aliphatic (entries 16,17) and allylic primarya lcohols (entries 18,19) also underwent the olefination to give the corresponding vinyl and conjugated allyl derivatives in moderate to good yields.…”

“…Benzyla lcohols weres electively convertedt og ive the corresponding E-stilbenes with high isolated yields (83-93 %, entries [13][14][15][16][17][18][19][20]. Naphthyl alcohols (entries 21,22) and heteroaromatic alcohols with furanyl, thienyl, pyridinyl, and benzo [1,3]dioxonyl groups (entries23-26) were also converted to the corresponding styryl derivatives in good to high yields (84-94 %). The internal olefination of cinnamyl alcohol gave trans,trans-1,4-diphenyl-1,3-butadiene in 92 % yield with high stereoselectivity.T he olefination of aliphatic alcohols with benzyl phenyl sulfone was also successful (entries 28-30).…”

“…Olefins are important structuralm oietiesi nc hemicals and synthetic intermediates;c onsequently,o lefination is one of the most important steps in both small-scaleo rganic synthesis and the production of chemicals in industry. [1] Amongv ariouso lefination protocols, the most convenientm ethodi st he olefination of carbonyl compounds with stabilized carbanions, such as Wittig reaction, [2] Horner-Wittig reaction, [3] Horner-Wadsworth-Emmons reaction, [4] Peterson reaction, [5] and Julia olefination. [6] The olefination of alcohols is well established owing to the availability of aw ide variety of substrates, and conventional methods use at wo-step procedure:s toichiometric oxidation of the alcoholt og ive ac arbonyl compound followed by olefination.…”

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

“…Chain extension was accomplished through a one-pot Swern oxidation/Wittig olefination protocol followed by hydrogenation to give ketone 127 . For further extension of the carbon chain and installation of the trisubstituted double bond, a modified Julia olefination with imidazole sulfone 128 was employed [100–102]. Thus, reaction of ketone 127 with the lithium anion of sulfone 128 and treatment of the obtained β-hydroxysulfone with SmI 2 led to olefin 129 as a 2:1 mixture of E/Z -isomers.…”

Convergent and stereospecific synthesis of complex skipped polyenes and polyunsaturated fatty acids

“…(15–18) While methods based on carbonyl olefination, alkylation and partial reduction of acetylenes have been employed in numerous campaigns in stereoselective synthesis, these often multi-step processes are each plagued by significant limitations in scope, selectivity and efficiency. Here, we describe a titanium-mediated stereoselective fragment coupling reaction that delivers a variety of complex skipped polyenes by a process that establishes five unique stereochemical relationships across the skipped polyene backbone in concert with C–C bond formation (Figure 2).…”