A systematic study into the Sonogashira cross-coupling of 1,1'-diiodoferrocene (fcI2) confirms that the Pd(0)-P((t)Bu)3 system provides a remarkable rate increase over Pd(0)-(PPh3)2. Attempts to couple 4-ethynylphenylthioacetate (2) with fcI2 instead produced a novel cyclic trimer of the former, from syn addition of S-Ac across C≡C.

Base-promoted 5-exo-dig cyclizations of aza-propargylglycinamides provided N-amino-imidazolin-2-one peptide mimics, which exhibited turn geometry in X-ray crystallographic and NMR spectroscopic analyses. Sonogashira coupling prior to cyclization afforded N-amino-imidazolin-2-ones with diverse 4-position aromatic substituents with potential to serve as Phe and Trp mimics.

Desmosine, a crosslinking amino acid of elastin, is an attractive biomarker for diagnosis of chronic obstructive pulmonary disease (COPD). In this study, the first total synthesis of (+)-desmosine was achieved in 11% overall yield in 13 steps utilizing stepwise and regioselective Sonogashira cross-coupling reactions.

A concise method for the synthesis of heterocycle-fused naphthoquinones such as naphtho[2,3-b]-furan-4,9-dione, 1H-benz[f]indole-4,9-dione, and naphtho[2,3-b]thiophene-4,9-dione was developed. This method employed Sonogashira coupling and tandem addition-elimination/intramolecular cyclization, and it enabled the preparation of versatile heterocycle-fused naphthoquinones from one substrate.

tert-Butoxyacetylene is shown to undergo Sonogashira coupling with aryl iodides to yield aryl-substituted tert-butyl ynol ethers. These intermediates participate in a [1,5]-hydride shift, which results in the extrusion of isobutylene and the generation of aryl ketenes. The ketenes are trapped in situ with multiple nucleophiles or undergo electrocyclic ring closure to yield hydroxynaphthalenes a...

The title technique, high-resolution magic angle spinning NMR of suspensions, constitutes a powerful new tool for investigating the structures and mobilities of immobilized species and, thus, for optimizing heterobimetallic catalyst systems, such as the Sonogashira coupling of terminal alkynes and aryl halides.

A set of carbazole substituted BODIPYs 2a-2c were designed and synthesized by the Pd-catalysed Sonogashira cross-coupling reaction. The effects of variation in the donor strength of various carbazoles were investigated by photophysical, electrochemical and computational studies. The electronic absorption spectra of BODIPYs 2a and 2c show charge transfer bands, which show red shift in polar solv...

A ring-closing alkene metathesis (RCM)/ oxyselenation-selenoxide elimination sequence was established to the sodium salts E- and Z-25 of the originally proposed structure for the recently isolated cytotoxin aruncin B (1), as well as to the sodium salt Z-34 of a related ethyl ether regioisomer; however, none of their corresponding free acids could be obtained. Their acid sensitivity, together wi...

Triarylborane substituted naphthalimide 3 was designed and synthesized by the Sonogashira cross-coupling reaction. The electronic absorption and emission spectra of the triarylborane naphthalimide 3 show red shifted absorption and emission as compared to 4-bromonaphthalimide 2. The sensing behaviour of 3 was studied for different anions. The triarylborane naphthalimide 3 selectively detects F(-...

Carbon–carbon bond formation by sp–sp or sp–sp crosscoupling is a key transformation in organic synthesis. Many methods, typically involving transition metal catalysis, are known, and the recent recognition of Richard F. Heck, Ei-ichi Negishi and Akira Suzuki by the Royal Swedish Academy of Sciences (Stockholm, Sweden) when they were awarded the Nobel Prize in Chemistry (2010) underlines the im...