PREPARATION OF HALIDES AND SULFONATES

Mandal, G.C. Bhattachariee. M. Chem. Coinmun., 2001, 1916. 

Tomimoto, K. Mase, T. Tetrahedron Lett., 2001, 42, 4849. 

Gellibert, F. Wagner. A. Mioskowski. C. Tetrahedron Lett., 2000, 41, 6049. 

For the conversion R-H - R-Hulogeii, see. Section 146 (Halides from Hydrides). 

Sawaguchi, M. Ayuba, S. Nakamura, Y. Fukuhara, T. Hara. S. Yoneda. N. 

SECTION 137 Halides and Sulf(mates from Acid Derivatives 

SECTION 138 Halides and Sulfonates from Alcohols and Thiols 

SECTION 140 Halides and Sulfonates from Alkyls, Methylenes, and Aryls 

f Zupan, M. J Org Chem, (1986), 51, 929 SECTION 141 Halides and Sulfonates from Amides 

SECTION 137 HALIDES AND SULFONATES FROM ACID DERIVATIVES 

SECTION 138 HALIDES AND SULFONATES FROM ALCOHOLS AND THIOLS 

Munyemana, F. Frisque-Hesbain, A.-M. DeVos, A. Ghosez. L. Tetrahedron Lett., 1989, 30, 3077. 

Purrinaton. S.T. Pittman, J.H. Tetrahedron Lett, 1988, 29, 6851. SOCIa. HMPA, RT 

SECTION 140 HALIDES AND SULFONATES FROM ALKYLS. METHYLENES AND ARYLS 

DBH = l,3-dibromo-5,5-dimethyl hydantoin Kuroboshi, M. Hivama. T. Chem. Lett., 1992, %T1. 

SECTION 145 HALIDES AND SULFONATES FROM HALIDES AND SULFONATES 

Desmaris, L. Percina, N. Cottier, L. Sinou.D. Tetrahedron Lett. 2003,44,7589. 

Hiegel. G.A. Rubino, M. Synth. Commun. 2002,32, 2691. PhCH2OH Nal, Amberlyst-15, rt, lh 

Atta-ur-Rahman Khan. K.M. Choudhary, M.I. Maharvi, G.M. Zia-Ullah Bayer, E. Synth. Commun. 2003,33, 2531. 

Firouzabadi, H. Iranpoor. N. Karimi, B. Hazarkhani, H. Synth. Commun.2003,33, 3671. 

Tajbakhsh, M. Hosseinzadeh, R. Lasemi, Z. Rostami, A. Synth. Commun. 2005, 35,2905. REVIEW 

HALIDES AND SULFONATES FROM ETHERS, EPOXIDES, AND THIOETHERS 

PodgorSek, A. Stavber, S. Zupan, M. Iskra, J. Tetrahedron Lett. 2006, 47, 7245. 

Akhrem. I. Orlinkov, A. Vitt, S. Christyakov, A. Tetrahedron Lett.2002,43,1333. 

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Preparation of Halides and Sulfonate Esters by Substitution Reactions... 

Carboxylic, and arylsulfonic acid halides react rapidly with pyridines generating 1-acyl- and 1-arylsulfonyl-pyridinium salts in solution, and in suitable cases some of these can even be isolated as crystalline, non-hygroscopic sohds. Solutions of these salts, generally in excess pyridine, are commonly used for the preparation of esters and sulfonates from alcohols, and of amides and sulfonamides from amines. 

Further examples of the preparation of halides from sulfonates are included in section 145 (Halides and Sulfonates from Halides and Sulfonates)... 

Propargylic acetates, halides, and sulfonates usually react with a double-bond shift to give allenes.34 Some direct substitution product can be formed as well. A high ratio of allenic product is usually found with CH3Cu-LiBr-MgBrI, which is prepared by addition of methylmagnesium bromide to a 1 1 LiBr-Cul mixture.35... 

Allylic stannanes can be prepared from allylic halides and sulfonates by displacement with or LiSnMe3 or LiSnBu3.146 They can also be prepared by Pd-catalyzed substitution of allylic acetates and phosphates using (C2H5)2AlSn... 

The main advantages of preparation of hydroxylamines through Af-alkylation of other hydroxylamines are versatility and predictable stereochemical outcome that allow the introduction of the hydroxyamino group at advanced stages of multistep syntheses. The use of nucleophilic displacement is however problematic for sterically hindered alkyl halides and sulfonates. Apart from several examples mentioned below, alkylation of hydroxylamines with tertiary alkyl halides does not take place. 

Alkylation of hydroxylamine with primary halides and sulfonates is rarely used nowadays for preparation of A-alkylhydroxylamines due to the competing formation of N,N-dialkylhydroxylamines. A number of older procedures have been reported with low to moderate yields of Al-alkylhydroxylamines. Yet, in many cases the reported low yields can be attributed to workup losses during distillation and crystallization steps rather than to the polyalkylation. Use of excess of hydroxylamine in reactions with primary alkyl halides (e.g. 3) improves the yields of monoalkylation (equation 2). Most of the examples of alkylation of hydroxylamine in good yield involve a substitution of an activated halogen atom at benzylic positions as well as in haloacetamides 4 leading to alkylhydroxylamines such as 5 where dialkylation rates are lower (equation 3). 

The general method for the preparation of organo-fluorine compounds from halides and sulfonates using anhydrous TBAF suffers from the fact that wherever possible an elimination reaction occurs decreasing the yield of the fluoro-substituted product. Traces of moisture present in anhydrous TBAF induce the formation of a hydroxy-substituted product. 1-Bromooctane... 

Nitriles may be prepared by several methods (1). The first nitrile to be prepared was propionitrile, which was obtained in 1834 by distilling barium ethyl sulfate with potassium cyanide. This is a general preparation of nitriles from sulfonate salts and is referred to as the Pelouze reaction (2). Although not commonly practiced today, dehydration of amides has been widely used to produce nitriles and was the first commercial synthesis of a nitrile. The reaction of alkyl halides with sodium cyanide to produce nitriles (eq. 1) also is a general reaction with wide applicability ... 

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