Search

Benzophospholes are obtained by intramolecular cyclization reactions of phosphinophenylalkynes involving a C—P bond cleavage and arylphosphination of the CC bond using a Pd(OAc)2/CuI bimetallic catalyst system.

Phospholes react with aldimines at 170 °C in the presence of mild Lewis acids to give C2-bridged biphospholes in good yields. The mechanism includes a series of [1,5] shifts of the P-substituents around the phosphole ring, a P–H + aldimine condensation, and the formation of a transient three-membered ring that dimerizes.

The first general synthesis of phospholides and annelated phospholides starting from open-chain precursors is presented.

The palladium-catalyzed reaction of 2-arylthiophenes (I) with alkynes (II) leads selectively to adducts (III) in moderate yields, whilst the reaction with thiophenes (IV) bearing a 2,6-dimethylphenyl or mesityl moiety proceeds via an other pathway affording products (V).

Silacycles play a very important role in modern organic chemistry and materials science. Construction of silacyclic skeletons via metal-mediated or catalyzed Si-C bond cleavage has attracted much recent attention. Several interesting and useful synthetic strategies have been reported in the literature. In this review, we have summarized recent developments on metal-mediated or catalyzed Si-C bond cleavage, which lead to the synthesis of silacycles, including silacyclobutenes, silacyclopentanes, silacyclopentadienes (siloles), 6-membered silacycles, and their derivatives.

The reaction of benzothiophenes and thiophenes with symmetrical diarylacetylenes leads to the cleavage of C—Br and C—S bonds and C—H activation in one pot.

A simple and efficient palladium-catalyzed three-component domino reaction of bromothiophenes with internal alkynes has been developed to produce benzo[b]thiophenes in moderate to good yields.

A novel four-step route towards phosphinines involves the cycloaddition of corresponding phospholes with diverse alkynes, followed by oxidation and oxygen—sulfur exchange at the phosphorus.

Reaction of zirconacyclopentadienes with 2-iodobenzyl halide and 2-iodobenzoyl halide afforded benzocycloheptene derivatives and benzocycloheptenone derivatives in good to high yields.

Zirconaindenes reacted with allyl halides in the presence of ZnX2 ( X= Cl or Br) and a catalytic amount of Pd(PPh3)4 to give naphthalene derivatives in good yield.

Using 1-R-3,4-dimethylphosphole-N-phenylmaleimide cycloadducts as synthetic equivalents of phosphinidenes [R–P], the following sequence has been developed: [R–P] + R1X → RR1PX → RR1P–OR2.

A practical and efficient method was developed for the synthesis of propargylamines in a one-pot procedure from aldehydes, amines, and alkynes by using CuI as catalyst and succinic acid as additive. By using this protocol, a wide range of propargylamines was obtained in high yields.

Under mild conditions, iodine promotes the direct alkylation of 1,3-dicarbonyl compounds with benzylic alcohols or benzylic acetates.

Under ‘open-flask’ and mild conditions, arenes condense smoothly with aromatic aldehydes in the presence of catalytic amount of FeCl 3 . The reaction tolerated a variety of substitutions and functional groups. This method provides a facile and direct access to symmetrical and unsymmetrical triarylmethane derivatives.

The one-pot, palladium-catalyzed, three-component coupling of aryl bromides, internal alkynes, and environmentally friendly K4[Fe(CN)6] provides an efficient and direct method for the preparation of β-arylalkenylnitriles.

Cyanation of aryl chlorides with potassium hexacyano-ferrate(II) catalyzed by cyclopalladated ferrocenylimine tricyclohexylphosphine complex has been described. This method is applicable to both activated and deactivated aryl chlorides. The corresponding aryl nitriles were isolated in good to excellent yields.

Zirconacyclopentadienes reacted with benzal halides in the presence of CuCl and dimethylpropyleneurea to give pentasubstituted cyclopentadienes in moderate to good yields. Treatment of zirconacyclopentadienes with 1,1-dibromo-1-alken-3-yne and 1,1-dibromo-1,3-alkadiene afforded fulvene derivatives in good yields.