The novel aromatic compounds cis-3-(2',4',5'-trimethoxyphenyl)-4-[(E)-2''',4''',5'''-trimethoxy-styryl]cyclohex-1-ene(1), cis-3-(3',4'-dimethoxyphenyl)-4-[(E)-3''',4'''-dimethoxystyryl]cyclohex-1-ene (2), a substance assigned the tentative structure cis-3-(3',4'-dimethoxyphenyl)-4-[(E)-2''',4''',5'''- trimethoxystyryl]cyclohex-1-ene (3),(E)-4-(3',4'-dimethoxypheny1)but-3-en-1-ol (5), (E)-4-(3',4'-dimethoxypheny1)but-3-en-1-yl acetate (6), and 8-(3',4'-dimethoxyphenyl)-2-methoxynaphtho-1,4- quinone (7) have been isolated from the rhizomes of Zingiber cassurnunav Roxb. (Zingiberaceae). The crystal structures of the cyclohexene derivative (1) and the quinone (7) have been determined from X-ray diffractometer data at 295 K and refined by block diagonal least squares to residuals of 0.046 (2099 'observed' reflections) and 0.093 (1246), respectively. Crystals of compound (1) are triclinic, P1, a 18.027(12), b 10.037(9), c 6.530(5) α, 84.22 (7), β 81.87 (6), γ 85.72 (6)�, Z 2. Crystals of the quinone (7) are monoclinic, P21/a, a 22.89 (1), b 8.022 (5), c 8.458 (5) �, β 91.98 (5)�, Z 4. Although the latter crystal structure determination is imprecise, due largely to the very small size of the crystal available, the solution is unambiguous. A simple two-step synthesis of the quinone (7) has been achieved.

The H-D exchange of aromatic amines and amides, including pharmaceutically relevant compounds such as acetaminophen and diclofenac, was investigated using CF3COOD as both the sole reaction solvent and source of deuterium label. The described method is amenable to efficient deuterium incorporation for a wide variety of substrates possessing both electron-donating and electron-withdrawing substituents. Best results were seen with less basic anilines and highly activated acetanilides, reflecting the likelihood of different mechanistic pathways.

A method has been developed for one-step ortho-selective ligand-directed H-D exchange, accompanied in some cases by concurrent acid-catalyzed electrophilic deuteration. This method is effective for deuteration of aromatic substrates ranging from ketones to amides and amino acids, including compounds of biological and pharmaceutical interest such as acetaminophen and edaravone. Use of a palladium catalyst featuring an NHC ligand is critical for the observed reactivity. Experimental evidence strongly suggests that palladium facilitates C-H activation of the aromatic substrates, a mechanism seldom observed under strongly acidic conditions. 2015 Elsevier Ltd. All rights reserved.

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Chiral dimeric tridentate NHC-amidate-alkoxide palladium(II) complexes, 3a and 3b, effected oxidative boron Heck-type reactions of aryl boronic acids with both acyclic and cyclic alkenes at room temperature to afford the corresponding coupling products with high enantioselectivities. The high degree of enantioselection, far superior to existing methods, stems from differences in the nonbonding interactions in the proposed transition states, due to the influence from bulky substituents of the alkene substrates and the "counter axial groups" of the palladium (II) catalysts. KeywordsN-heterocyclic carbene ligand; amidate ligand; oxidative palladium(II) catalysis; boron-Heck; asymmetric catalysis; carbon-carbon bond formation