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The title ligand in combination with Pd(II) is found to be highly effective for the Suzuki-Miyaura reaction of aryl bromides and activated aryl chlorides.

Topsendine A (Ia), B (Ib), C (IV), D (IIa), E (III) and F (IIb) as well as 2-methyl-12-(pyridine-3-yl)dodecanal (IIc) are isolated and their structures are elucidated.

The title synthesis is applicable to a broad substrate scope under the present mild and effective conditions.

A broad spectrum of 2-substituted benzothiazoles is available in the presence of sodium sulfide, where a wide range of functional groups is tolerated at the arene moieties of the substrates.

Aryl halides react with phenylboronic acid affording biphenyl compounds (III) in excellent yields.

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki–Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain corresponding biaryls in excellent yields. The recycling of the polymer-bound catalyst was tested without adding palladium.

The Pd-catalyzed trans-selective monoalkynylation of 1,1-dihalo-1-alkenes with XZnC CSiMe3, where X is Br or Cl, can proceed generally in excellent yields in the presence of Pd(DPEphos)Cl2 or Pd(dppf)Cl2, and subsequent alkylation with methyl- and ethylzincs can proceed in excellent yields with ≥98% retention of configuration in the presence of Pd(tBu3P)2 as a catalyst.

Trans -selective monoarylation of 1,1-dibromo- and 1,1-dichloro-1-alkenes ( 1 ) can be achieved in >80% yields and in ≥98–99% stereoselectivity with arylzinc bromides in the presence of a catalytic amount of Cl 2 Pd(DPEphos) or Cl 2 Pd(dppb), the former permitting cleaner and higher yielding reactions. Although THF is a generally satisfactory solvent, ether and toluene are superior to THF in some cases. The second substitution of ( Z )-α-bromostyrenes ( 3 ) with alkylzincs in the presence of 2 mol% of Pd( t Bu 3 P) 2 proceeds to give the corresponding 2 in >90% yields and in ≥98–99% stereoselectivity. Although somewhat less satisfactory, the use of Cl 2 Pd(DPEphos) permits a one-pot tandem arylation–alkylation.

[reaction: see text] trans-Selective (or=98%) monoalkynylation of 1,1-dibromo-1-alkenes and 1,1-dichloro-1-alkenes catalyzed by Cl(2)Pd(DPEphos) followed by stereospecific methylation with Me(2)Zn or MeZnX (X= Cl or Br) catalyzed by Pd((t)()Bu(3)P)(2) provides an efficient and stereoselective (or=98%) route to 5, convertible to a wide variety of enynes and conjugated dienes. In the cases of 1,1-dibromo-1-alkenes, the Sonogashira alkynylation may also be satisfactory, but it is distinctly less satisfactory than the alkynylzinc reaction in cases where 1,1-dichloro-1-alkenes are used.