Condensation of 5-nitro, 3-chloro-, and 5-chlorosalicylic acid with formaldehyde afforded dimeric disalicylmethanes which were O-methylated with dimethyl sulfate and oxidized with chromium(VI) oxide to give the diarylketones 10, 11, 12. Wittig reaction with ylides obtained by deprotonation of alkyltriphenylphosphonium salts with sodium bis (trimethylsilyl)amide yielded a series of diarylalkenes...

A three-step procedure has been developed for preparing ortho-alkoxybenzaldehydes from ortho-fluorobenzaldehydes that tolerates the use of sterically hindered sodium alkoxide nucleophiles. The protocol is modular and operationally convenient. The ortho-alkoxybenzaldehyde products can be converted in one additional step to ortho-alkoxystyrenes by a Wittig reaction. These styrenes are precursors ...

An efficient and attractive synthesis of a series of novel poly-functionalized phosphorus zwitterions was achieved via three-component reactions of the corresponding functional nucleophiles, aldehydes, and Bu(3)P in the presence of acidic promoter. These polysubstituted zwitterions could regioselectively undergo further transformations to synthetically important furanonaphthoquinones and relate...

The main synthetic routes towards vinylphosphonium salts and their wide applications in organic synthesis are discussed in this review. Particular attention is paid to the use of these compounds as building blocks for the synthesis of carbo- and heterocyclic systems after their prior transformation into the corresponding phosphorus ylides, followed by the intramolecular Wittig reaction with var...

D-Ribose was converted into 3 novel carbobicyclic nucleosides bearing a bicyclo[4.3.0]nonane framework in 16-19 steps with 5-12% overall yields involving a Wittig olefination and an intramolecular Diels-Alder reaction as the key steps. The present synthesis also provides an efficient entry for chiral hydrindenones. The conformation studies of these carbanucleosides and their bio-evaluation as p...

An efficient three-step synthesis of d-mannoheptulose was successfully accomplished from 2,3,4,5,6-penta-O-benzyl-d-mannose. First, an olefinated sugar was prepared from 2,3,4,5,6-penta-O-benzyl-d-mannose via a Wittig reaction. Second, the key step, a 2-hydroxyoxirane product was unexpectedly obtained by oxidation of the olefinated sugar with potassium permanganate in aqueous acetone. Finally d...

The title compound, C(18)H(20)O(4), was synthesized by a Wittig-Horner reaction of diethyl 3,4-dimeth-oxy-benzyl-phosphate and 3,5-dimeth-oxy-benzaldehyde. In the crystal, the dihedral angle between the two aromatic rings is 2.47 (12)°. All the meth-oxy groups are almost coplanar with the aromatic ring to which they are attached [C-C-O-C torsion angles = -2.8 (3), -5.2 (4), -176.3 (2) and -178....

The title compound, C(28)H(22)O(6)S(2)·2C(6)H(13)N·2H(2)O, was prepared by the reaction of a Wittig reagent and 2-formyl-benzene-sulfonic acid. The main molecule lies about an inversion centre at the midpoint of the C-C bond between the inner benzene rings. The mol-ecular conformation is stabilized by intramolecular hydrogen bonds. The crystal structure is further stabilized by O-H⋯O and N-H⋯O ...

The first total synthesis of ratjadone was achieved using a highly convergent approach joining three subunits together with a Wittig olefination and a selective Heck reaction as the pivotal steps. Besides establishing a robust and reliable route for the synthesis of this orphan ligand, the configuration of unknown stereocenters could also be determined. This synthesis not only provides an addit...

The reaction of ferrocenyldiphenylphosphine with styrene oxide in ethanol gives, as the major product, ferrocenyl(phenyl)(l,2-diphenylethyl)phosphine oxide (5, R = Ph), the result of a rearrangement involving phenyl migration from phosphorus to adjacent carbon in the decomposition of a vinylphosphonium ion arising from protonation and subsequent elimination of water from the initially-formed ph...