Multisubstituted Olefins: Platform Synthesis and Applications to Materials Science and Pharmaceutical Chemistry

Abstract

The concept of platform synthesis has been successfully demonstrated as a useful strategy for making multisubstituted olefins in a programmable and diversity-oriented format. As well as applications to the synthesis of pharmaceutically important molecules such as tamoxifen and CDP840, applications to materials science, which have led to the discovery of interesting fluorescent materials and properties, are also described.

Interrogation of a Sonogashira Cross-Coupling of 8-Bromoguanosine with Phenylacetylene on Amberlite: Evidence for Pd/Cu Ion Binding and Propagation of Pd/Cu Nanoparticles

“…The addition of three equivalents of 1 with respect to Pd(η 2 -dba)(PPh 3 ) 2 (in DMSO-d 6 ), under identical conditions, increased the intensity of the signals at δ 17.2 and 17.5 ppm, without affecting their ratio, at the expense of Pd(η 2 -dba)(PPh 3 ) 2 (spectrum B, Figure 2). The reaction of 2 with Pd(η 2 -dba)(PPh 3 ) 2 in DMF is shown in spectrum C ( Figure 2), which again shows the formation of two new phosphorus signals at ca.…”

“…[2] The Sonogashira cross-coupling reaction [3] -the union of a Csp atom with a Csp 2 atom, mediated by a Pd 0 catalyst and Cu I cocatalyst, to give vinyl and aryl substituted acetylenes-is an extremely versatile transformation. [4] It has been employed successfully to prepare natural products, [5] pharmaceutical agents, [6] and advanced materials and bioprobes. [7] Given these extensive applications, new reaction conditions continue to emerge, particularly reactions that can be conducted on solid-support allowing the metal catalysts/cocatalysts, for example, Pd 0 and Cu I , and byproducts to be removed easily from the desired product.…”

Multicoloured Thiophene Based AIEgens: Single Crystal Structure Elucidation, Spectral Behaviour and DFT Studies

“…The occurrence of π–π stacking interactions lead to the formation of aggregative species such as delocalized excitons and excimer that has always been a hindrance in the development of efficient OLEDs . In contrast to ACQ, various mechanisms have been proposed supporting AIE behaviour in luminophores viz restriction of intramolecular rotation,, formation of J‐aggregates, intramolecular planarization, inhibition of photoisomerization, photocyclization and blockage of nonradiative relaxation pathways of the excited species . In general, AIE materials have twisted type structure that avoids possible intermolecular π–π interactions.…”

Silver sequestration of halides for the activation of Pd(OAc)2 catalyzed Mizoroki‐Heck reaction of 1,1 and 1,2 ‐ Disubstituted alkenes

“…The Mizoroki‐Heck arylation of monosubstituted alkenes is a fast and well studied reaction while that of 1,1 and 1,2‐disubstituted alkenes is relatively less explored. 1,1,2 –Trisubstituted and 1,1,2,2,‐tetrasubstituted aryl alkenes are an important structural motif in several bioactive molecules, functional materials, OLED and various organic electroluminiscent devices . Several methodologies are available for the synthesis of these 1,1,2‐ and 1,1,2,2‐ aryl alkenes but they give mixtures of E‐Z stereoisomers and isomeric purity is essential for bioactivity .…”