Recent Developments of Wittig Reaction in Organic Synthesis Through Tandem Or Sequential Processes

Recent Developments Towards the Synthesis of Varitriol: An Antitumour Agent from Marine Derived Fungus Emericella Variecolor

“…Amongst In the end, two fragments (olefinic compound 62 and aromatic triflate 8) were coupled using the earlier reported procedure (Heck coupling) [32] employing Pd (PPh 3 ) The synthesis started with tetrahydro furan derivative which had been previously reported by Yadav and coworkers [47] was subjected to fluorination using DAST. The method developed [48] Recently, tandem strategies employing Wittig olefination in combination with many other reactions has been widely utilized in organic syntheses, particularly natural product syntheses which have been well reviewed by Parvatkar et al [49]. Shaw and coworkers has disclosed an efficient route for their second generation synthesis of varitriol (+)-5 from D-ribose wherein THF moiety was constructed via one-pot Wittig olefination and highly diastereoselective intramolecular oxa-Michael addition approach (Scheme Norbert and coworkers designed the synthesis of (+)-varitriol via reagent-controlled introduction of all stereogenic centers using combined coinage metal catalyst approach [52].…”

Diastereoselective synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives following hetero-Diels–Alder reaction andin vitroanticancer studies

“…Wittig reaction of 8(a–h) and 10(a–g) with methyl triphenyl phosphonium bromide in BuLi afforded 3-vinyl-2 H -chromene derivatives 2(a–h) and 2′(a–h) in good yield. 33 Compounds 2(a–h) and 2′(a–f) were successfully characterised by 1 H, 13 C NMR and IR. For example, the aldehydic proton which appears at 9.66 ppm for compound 8a vanishes in the 1 H NMR of compound 2a.…”

6. Experimental procedures for conducting organic reactions in continuous flow

“…A convenient and selective way of forming a carbon-carbon double bond is through the Wittig reaction and its modifications [1,2]. Although easily performed in batch, the Wittig reaction could be incorporated in a total synthesis using continuous flow.…”

“…In continuous flow, an aldehyde (1) and a phosphoniumylide (2) are introduced into the microreactor, where they react to form the corresponding unsaturated Wittig product (3). The Wittig reaction is an example of a very selective reaction, producing no side-products.…”