Enantioselective phosphination and hydrophosphonylation reactions between azomethine imines and diarylphosphine oxides or dialkyl phosphites were respectively developed by the use of a chiral squaramide as the hydrogen bonding organocatalyst, which afforded two types of phosphorus containing product in high yields with good to excellent enantioselectivities.

Hail boration! 2-Dimethylaminopyridine-ligated dihaloborocations [X2B(2-DMAP)](+) with a strained four-membered boracycle were used for the haloboration of terminal and dialkyl internal alkynes (see scheme). Esterification then provided vinyl boronate esters as useful precursors to tetrasubstituted alkenes. Following mechanistic studies, the scope of the haloboration was expanded simply by vari...

The electrochemical behavior of quinoline in anhydrous liquid ammonia was investigated by cyclic voltammetry and controlled potential coulometry. In the absence of added alkylating agent, quinoline is reduced in two steps to yield the radical anion and dianion both of which undergo further chemical reaction. The radical anion species dimerizes to form the dimeric dianion which is stable in the ...

[reaction: see text] A novel palladium-catalyzed coupling reaction between two Csp(3)-Csp(3) centers has been investigated. This protocol is initiated by the oxidative addition of an alpha-halo carbonyl compound to a palladium(0) species, followed by the double transmetalation. The key dialkyl palladium intermediate undergoes reductive elimination to form the desired coupling product.

A series of monoligated L·Pd(II)(Ar)X complexes (L = dialkyl biaryl phosphine) have been prepared and studied in an effort to better understand an unusual dearomative rearrangement previously documented in these systems. Experimental and theoretical evidence suggest a concerted process involving the unprecedented Pd(II)-mediated insertion of an aryl group into an unactivated arene.

4-(Dimethylamino)benzaldehyde is alkylated at the N atom by dialkyl sulfates, MeI, or Me3O BF4. In contrast, ethylation by Et3O BF4 occurs selectively at the O atom yielding a quinoid iminium ion. 4-(Diethylamino)benzaldehyde is alkylated only at O by either Et or Me oxonium reagent. The iminium salts are prone to hydrolysis giving the corresponding hydrotetrafluoroborates. Five crystal structu...

Organic base-catalyzed reaction of (S)-N-tert-butanesulfinyl (3,3,3)-trifluoroacetaldimine with dialkyl malonates was found to be effective for synthesis of both (S,S(S)) and (R,S(S)) β-aminomalonates in high yield with good to excellent diastereoselectivity (76-98% de). The products of this Mannich reaction provide direct access to β-trifluoromethyl-β-alanine of either (R) or (S) absolute conf...

A water-soluble squaric acid dialkyl diester derivative is presented, which enables one-pot, two-step amine-selective protein conjugation reactions with (functional) amines in water. This reagent not only allows all-aqueous protein modifications, but also tolerates e.g. hydroxyl groups and can also be used for the modification of proteins with water-insoluble amines.

We synthesized and characterized bromide-bridged Pd(III) chain complexes, [Pd(en)2Br](MalCn-Y)2·H2O (en = ethylenediamine; MalCn-Y = dialkyl sulfomalonate; n: the number of carbon atoms) (n = 7 and 12). The compound with n = 7 showed charge-bistability near room temperature. In addition, it is shown that the Pd(III) state is maintained in the thin film state.