We report that Zn[N(SiMe 3 ) 2 ] 2 is a mild ammonia equivalent and base for the palladium-catalyzed amination of aryl halides and triflates. In contrast to LiN(SiMe 3 ) 2 , the combination of Zn[N(SiMe 3 ) 2 ] 2 and LiCl coupled with aryl halides and triflates containing base-sensitive functionality in high yields. In addition, aryl bromides coupled with aryl and alkylamines with the combination of Zn[N(SiMe 3 ) 2 ] 2 and LiCl as base. These aminations occurred without racemization of the enolizable stereocenter of an optically active ester.Palladium-catalyzed C-N bond formation has developed into a general and efficient way to prepare arylamines from aryl halides. [1][2][3][4][5] While a variety of amines and other nitrogen nucleophiles undergo this reaction in the presence of base, ammonia does not form primary arylamines. Thus, reactions have been conducted with ammonia surrogates, such as allylamine 6 or benzophenone imine. 7,8 Recently, we reported the synthesis of primary arylamines catalyzed by Pd(dba) 2 and P(t-Bu) 3 with lithium bis(trimethylsilyl)amide (LiN-(SiMe 3 ) 2 ) as an ammonia equivalent. This reagent is inexpensive, and the aryl silylamine is easily deprotected. 9 Buchwald reported a similar coupling with catalysts containing 2-phosphinobiphenyl ligands. 10 While LiN(SiMe 3 ) 2 coupled with a range of aryl halides under mild conditions with low catalyst loading, the strong basicity of the reagent prevented reactions with aryl halides bearing base-sensitive functional groups or enolizable hydrogens. 9,10 Recently, we developed conditions for the coupling of zinc enolates with aryl halides. 11 The functional group compatability of the R-arylation of carbonyl compounds with zinc enolates was greater than that with alkali metal enolates. 12 With this result in mind, we sought conditions to use zinc

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The mixed solvent 4,4'-dipyridyl/phenol forms two immiscible phases with hydrocarbons such as alkane or olefin at room temperature, whereas at high temperature these two phases turn into one homogeneous phase. If this solvent mixture is used for the title reaction of benzyl alcohols (I) with alkenes (II) in the presence of a rhodium/phosphine catalyst and 2-amino-4-picoline as a chelation auxiliary, the mixture, homogenic at 150 °C during the reaction, separates after the reaction into two phases at ambient temperature. The picoline and the rhodium complex stay in the polar phase (4,4'-dipyridyl/phenol), whereas the formed ketone largely stays in the nonpolar hydrocarbon. Therefore, the catalyst can be separated from ketone. With 4-diphenylphosphinobenzoic acid as ligand, the reactivity of the catalyst is retained for repeated uses.

Page 1. Experimental procedures, spectral and analytic data. S2 2. Data for optimization of the coupling of aryl halides with zinc silylamide S10 S2 General Methods. Most reactions were conducted using standard drybox techniques, but a procedure for conducting reactions without a drybox is also provided. 1 H and 13 C NMR spectra were recorded on a Bruker DPX 400 MHz Spectrometer with tetramethylsilane or residual protiated solvent as a reference. GC and GC/MS analyses were conducted with an HP-1 methyl silicone column. Yields for final products in Tables 2 and 3 refer to isolated yields and are the average of at least two runs. Zinc bis[bis-(trimethylsilyl)amide], 1 (S)-2-(6-Methoxy-naphthalen-2-yl)-propionic acid methyl ester 2 were prepared according to the known procedures. Among aryl triflates, 3-methylphenyl trifluoromethanesulfonate, 3-methoxyphenyl trifluoromethanesulfonate, 3-(trifluoromethyl)phenyl trifluoromethanesulfonate, 4-cyanophenyl trifluoromethanesulfonate, and 3-cyanophenyl trifluoromethanesulfonate were prepared according to the known procedure. 3 All other chemicals were used as received from commercial sources. Synthesis of Zinc Bis[bis(trimethylsilyl)amide]. 1 In a 150 mL Schlenck flask were placed zinc chloride (6.81 g, 50.0 mol) and sodium bis(trimethylsilylamide) (18.34 g, 100.0 mol) in a drybox. The flask was removed from the drybox, and Et 2 O (60 mL) was introduced via syringe under nitrogen atmosphere. The reaction mixture was stirred at 50°C for 5 h. Cooled to ambient temperature, the flask was brought into the dry box, and the precipitate was filtered through Celite on fritted glass. The collected solid was washed with Et 2 O (15 mL). The combined ether filtrate was evacuated at reduced pressure, and the the resulting crude product was purified by vacuum distillation (72-74 °C at 0.4-0.5 mmHg, lit. 1 103 °C at 2-3 mmHg) to give colorless liquid of Zn[N(SiMe 3 ) 2 ] 2 (13.12 g, 68%). 1 H NMR (CDCl 3 ) δ 0.10 (s); 13 C NMR (CDCl 3 ) δ 4.16. Synthesis of 2-(6-Methoxynaphthalen-2-yl)propionic acid methyl ester. 2 To a 50 mL round bottom flask containing (S)-(+)-6-methoxy-α−methyl-2-naphthaleneacetic acid (1.10 g, 4.78 mmol) was added 50 mL of MeOH and a catalytic amount of conc. H 2 SO 4 . The reaction mixture was stirred at room temperature, and the reaction progress was monitored by TLC. Upon completion, the reaction mixture was concentrated to half the volume in a rotary evaporator. Water (5 mL) was added, and the mixture was extracted with CH 2 Cl 2 (3×10 mL). The combined organic layers were washed with water (3×10 mL), brine (10 mL), and dried over MgSO 4 . The solvent was removed in vacuo to give white solid of title compound (1.06 g, 91%) 1

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