Binaphthyl iodide

Enantiopure 1,l -binaphthyl derivatives were prepared starting from binaphthyl iodides or -triflates without loss of enantiomeric purity. The same reaction performed under oil-bath heating was associated with slower reactions and lower yields [157]. 

Methyl vinyl ketone (195) underwent Heck reaction with cyclic iodonium salt 196 in the presence of Pd(OAc)2 and proton sponge to give binaphthyl iodide 197 in 81% yield (Scheme 22.45) [68]. When the base was switched from proton sponge to EtsN, annulated product 198 was produced in 88% yield the conditions smoothly catalyzed not only the intermolecular Heck reaction but also intramolecular Heck reaction of 197. It is noteworthy that 196 is utilized as a synthetic equivalent of 2,2 -diiodobinaphthyl. 

Unactivated aryl iodides undergo the conversion Arl — ArCHj when treated with tris(diethylamino)sulfonium difluorotrimethylsilicate and a palladium catalyst.131 A number of methods, all catalyzed by palladium complexes, have been used to prepare unsymmetrical biaryls (see also 3-16). In these methods, aryl bromides or iodides are coupled with aryl Grignard reagents,152 with arylboronic acids ArB(OH)2,153 with aryltin compounds Ar-SnR3,154 and with arylmercury compounds.155 Unsymmetrical binaphthyls were synthesized by photochemically stimulated reaction of naphthyl iodides with naphthoxide ions in an SrnI reaction.156 Grignard reagents also couple with aryl halides without a palladium catalyst, by the benzyne mechanism.157 OS VI, 916 65, 108 66, 67. 

On reaction with sodium sulfide in DMF, easily accessible racemic 2,2 -bis(bromomethyl)-l,l -binaphthyl 168 afforded dihydrothiepine 23 in 99% yield (Scheme 26) <1994JOC1326>. The racemic thiepine 23 was resolved by liquid chromatography on triacetylcellulose on a preparative scale to give (R)-(—)-23 (90% yield, 97% ee) and (. )-(+)-23 (83% yield, 100% ee) (Section 13.03.4.2). Alternatively, reaction of diamine ( 5)-(—)-198, which is derived from an enantiomer (.) )-(+)-197, and methyl iodide in MeCN and subsequent reaction with Na2S-9H20 in DMF gave ( S)-(+)-23 in 35% yield. 

Dichloroiodo)arenes may also be converted to (diacetoxyiodo)arenes upon treatment with mercuric acetate. This approach and also perborate oxidation of iodides were used for the preparation of some chiral l,l -binaphthyl derivatives [28]. 

In 2000, Rajanbabu et al. published the synthesis and coordination chemistry of the first chiral NHC containing a l.T-binaphthyl unit as the chiral element (Scheme 24) [69]. It contains two imidazolium rings linked to the l,T-binaphlhyl backbone in the 2 and 2 position through methylene bridges. This linkage was achieved by nucleophilic substitution and the imidazolium salts subsequently generated in an N-quaternization step with methyl iodide. 

Rychnovsky and his group have recently developed new synthetic methods that lead to the total syntheses of the polyene macrolides roxaticin [2], roflamycoin [3], and filipin III [4]. The polyol chains of all three natural products were constructed by iterative, stereoselective alkylation of lithiated cyanohydrin acetonides and subsequent reductive decyanation, illustrated here by the synthesis of the polyol framework of filipin III (1) (Scheme I). The bifunctional cyanohydrin acetonide 2, prepared by ruthenium/BINAP catalyzed enantioselective hydrogenation of the corresponding ) -keto ester (BINAP = [ 1,1 -binaphthyl]-2,2 -diylbis(diphenylphosphane)), is deprotonated with LiNEt2 and alkylated with 2-benzyloxy-l-iodoethane. The alkylation product 3 is converted by a Finkelstein reaction into the iodide 4, which is used to alkylate a second... 

Unsymmetrical binaphthyls were synthesized by photochemically stimulated reaction of naphthyl iodides with naphthoxide ions in an SrnI reaction. " Methyl chloroacetate coupled with aryl iodides under electrolysis conditions, using a nickel catalyst. " " Unsymmetrical biaryls were prepared from two aryl iodides using a Cul catalyst and microwave irradiation. " ... 

D. (RM+ -DiphenylphosphinyM -methoxy-hl -binaphthyl (5). A 250-mL round-bottomed flask is charged with crude 4, 5.55 g (40.2 mmol) of potassium carbonate (K2C03), and 66 mL of acetone. To this mixture is added 2.5 ml. (40.2 mmol) of methyl iodide (Mel) (Note 17). The reaction mixture is refluxed for 3 hr. After the reaction is cooled to room temperature it is filtered through a Celite pad (Note 18), and the filter cake is washed with diethyl ether (EtgO). The filtrate is concentrated under reduced pressure to give 6.88 g of 5 as a brown powder (Note 19). This crude material is carried on to the next step without purification, assuming 100% yield. 

The light-induced reactions of fluoro-, chloro-, and bromo-naphthalenes have been studied in the nucleophilic solvents methanol and diethylamine.83 The fluoro-derivative yields substituted products from the naphthalene singlet state, but the other halogenonaphthalenes react from the Tx state to give mainly the radical products naphthalene and binaphthyl, although some substitution is observed. Attempts to quench the reactions led to anomalous behaviour in that the quantum yields were actually increased in the presence of several potential triplet quenchers.84 85 Aryl iodides have been reported to react rapidly with potassium dialkyl phosphates in liquid ammonia when irradiated with 350 nm wavelength light.86 Dialkyl arylphosphonates are formed in 87—96% yield... 

Ozonation of pentaphene (11) (shown below) in methylene chloride at —78°C. with one mole equivalent of ozone led to a peroxidic mixture which on oxidative workup led to 2,2 -binaphthyl-3,3 -dicarboxaldehyde (16) (16%), 2,2 -binaphthyl-3,3 -dicarboxylic acid (17) (16%), and phthalic acid (13) (2%) reductive workup (sodium iodide in acetic acid) gave 16 (25% ). In both cases, 28% of unreacted 11 was recovered. Ozonation of 11 with 4 mole equivalents of ozone followed by oxidative workup gave 2,2, 4,4, 5,5 -hexacarboxybiphenyl (18) (53%) and phthalic acid (13 ) (9% ). 

Related Reagents. Lithium Aluminum Hydride-(2,2 -Bipy-ridyl)(l,5-cyclooctadiene)nickel Lithium Aluminum Hydride-Bis(cyclopentadienyl)nickel Lithium Aluminum Hydride-Boron Trifluoride Etherate Lithium Aluminum Hydride-Cerium(III) Chloride Lithium Aluminum Hydride-2,2 -Dihydroxy-l, E-binaphthyl Lithium Aluminum Hydride-Chromium(III) Chloride Lithium Aluminum Hydride-Cobalt(II) Chloride Lithium Aluminum Hydride-Copper(I) Iodide Lithium Aluminum Hydride-Diphosphoms Tetraiodide Lithium Aluminum Hydride-Nickel(II) Chloride Lithium Aluminum Hydride-Titanium(IV) Chloride Titanium(III) Chloride-Lithium Aluminum Hydride. 

Azoles such as pyrrole (57), carbazole (58), and indole can be N-arylated in the presence of DPPF [48]. Various N-arylated indoles were prepared conveniently by N-arylation of indole with aryl iodides, bromides, chlorides, and triflates. Suitable ligands are selected from bulky biphenyl- or binaphthyl-based phosphines IV-12, rV-14, and VI-3 depending on the kinds of aryl halides used [49],... 

Bis(octadecyloxy)-6,6 -dibromo-l,r-binaphthyl, (/ )-27, a monomer with 18-carbon alkyl groups, is prepared from the reaction of (/ )-14 with 1-iodo-octadecane in order to make the subsequent polymers soluble. We have found that polymers made from the monomers with shorter alkyl substituents such as 6- or 10-carbon chains are not soluble. The specific optical rotation of (/f)-27 is [ ][, = +20.5 (c = 1.0, CH2CI2). Polymerization of ( )-27 with 1,4-bisethynylbenzene, 28, in the presence of palladium dichloride and cuprous iodide [32] produces a low-molecular-weight polymer (/ )-29a (Scheme 12). GPC shows that its molecular weight is = 7400 and = 3800 (PDI = 2.0). The specific optical rotation of (/ )-29a is [ ] = -154.9 (c = 1.0, CH2CI2). Rac-9ai. is obtained from the cross-... 

We have applied cross-coupling reactions of alkynes and aryl bromides to prepare the structurally well-defined polybinaphthyl crown ethers. A racemic binaphthyl crown ether monomer roc-75 [18,62] is polymerized with roc-33 in the presence of tetrakis(triphenylphosphine) palladium(O) and copper iodide to generate a polybinaphthyl crown ether 76 (Scheme 32). This polymer is soluble in organic solvents and has been characterized by various spectroscopic methods. GPC analysis shows that 76 has a molecular weight of 30,000 and M = 12,000 (PDI = 2.4). The UV spectrum of the polymer shows the maximum absorptions - max = 246, 300, and 354 nm. 

The intramolecular version of this reaction is known [2]. It must be noted that in the initial reactions, P(o-To1)3 was used as part of the catalyst however, some diphosphane complexes such as 1,1 -bis(diphenylphosphino)ferreocene (dppf) and 2,2 -bis(diphenylphosphino)-l,l -binaphthyl (BINAP) showed improvements for the coupling of aryl bromides and iodides with primary alkyl amines [2]. These studies are comprehensively detailed in Ref. [2]. 

Copper-catalysed enantioselective conjugate addition of Grignard reagents to a,p-unsaturated methyl esters is sueeessfully carried out to provide p-substituted chiral esters in good yields and with excellent enantioselec-tivities (Scheme 15.24). A combination of copper iodide and commercially available chiral (R)-2,2 -bis(di-p-tolyl-phosphino)-l,l -binaphthyl (Tol-BINAP) is also effective. ... 

Keywords Aryl iodides, aliphatic amines, CuBr, racemic-1,1 -binaphthyl-2,2 -diol (rac-BINOL), K3PO4, N,N-Dimethyl formamide (DMF), room temperature, coupling reaction, amination, N-arylation of aliphatic amines... 

A flask was charged with CuBr (28 mg, 0.2 mmol), rac-l.l -binaphthyl-2.2 -diol (1 57 mg, 0.2 mmol), K3PO4 (424 mg, 2 mmol), aryl iodide (2 1 mmol), amine (3 1.5 mmol), and DMF (1 mL) under nitrogen atmosphere. The flask was sealed and the mixture was allowed to stir under the nitrogen atmosphere at room temperature for stipulated time-period of 3 -11 h. After completion of the reaction, the mixture was diluted with ethyl acetate, the solution was filtered, and the inorganic salts were removed. The residue obtained on removal of the was purified by column chromatography on silica gel using petroleum ether/ethyl acetate (60 1 to 4 1) as eluent to furnish pure A -aryl amine 4 with yields of 38-85%. The products were characterized from spectral smdies. 

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