PREPARATION OF ALKYLS, METHYLENES, AND ARYLS

This chapter lists the conversion of functional groups into methyl, ethyl, propyl, etc. as well as methylene (CH2), phenyl, etc. 

SECTION 61 ALKYLS, METHYLENES AND ARYLS FROM ALKYNES 

Ohishi, T. Kojima, T. Matsuoka, T. Shiro, M. Kotsuki. H. Tetrahedron Lett., 2001, 42, 2493. 

Related Methods Alkyls, Methylenes and Aryls from Ketones (Section 72) 

SECTION 61 Alkyls, Methylenes, and Aryls from Acetylenes 

Review Cobalt Mediated 2+2+2 Cycloadditions A Maturing Synthetic Strategy  

ALKYLS, METHYLENES, AND ARYLS FROM ALCOHOLS AND THIOLS 

Fasseur, D. Cherepy, N. Couturier, D. Tetrahedron Lett., 1989, 

Kajiwara, K. Shirae, Y. Sakamoto, M. Fujita, T. Synlett2008, 2711. 

Toshima, K. Ohta, K. Ohtake, T. Tatsula. K. Tetrahedron Lett., 1991, 32, 391. 

Taguchi, H. Takami, K. Tsubouchi, A, Takeda. T. Tetrahedron Lett. 2004, 45,429. 

Sartori. G. Bigi, R Pastorio, A. Porto, C. Arienti, A. Maggi, R. Moretti, N. Gnappi, G. Tetrahedron Lett., 1995, 36, 9177 

TMAD= MezNCON=NCONMez DHTD = 4,7-dimethyl-3,5,7-hexahydno-l,2,4,7-ietra2ocin-3,8-dione Tsudoda. T. Nagaku, M. Nagino, C. Kawamura, Y. Ozaki, F. Hidd, H. It6, S. Tetrahedron Utt., 1995, 36, 2531 

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No examples of the preparation of ethers and epoxides by replacement of alkyl, methylene and aryl groups occur in the literature. For the conversion RH —ROR (R=alkyl, aryl etc.) see section 131 (Ethers from Hydrides)... 

Examples of alkylation, dealkylation, homologation, isomerization, and transposition are found in Sections 1, 17, 33, and so on, lying close to a diagonal of the index. These sections correspond to such topics as the preparation of acetylenes from acetylenes carboxylic acids from carboxylic acids and alcohols, thiols, and phenols from alcohols, thiols, and phenols. Alkylations that involve conjugate additions across a double bond are found in Section 74 (alkyls, methylenes, and aryls from olefins). 

This section contains alkylations of ketones and protected ketones, ketone transpositions and annulations, ring expansions and ring openings, and dimerizations. Conjugate reductions and Michael alkylations of enone are listed in Section 74 (Alkyls, Methylenes, and Aryls from Alkenes). For the preparation of enamines or imines from ketones, see Section 356 (Amine-Alkene). 

As in the Grignard reaction we may use any aliphatic aldehyde, ketone, ester or acid chloride, or an aryl compound of the same type and also, we may use either alkyl magnesium halides or aryl magnesium halides the synthesis makes possible the preparation of practically any desired secondary or tertiary alcohol either aliphatic or aromatic. Also if formaldehyde, in the form of its polymer, tri-oxy methylene, is used in the second reaction we will obtain primary alcohols. In the third reaction formic acid esters yield secondary instead of tertiary alcohols. These syntheses of alcohols by the Grignard reaction give us an idea of its importance in synthetic work. 

Preparation of A -alkylanilines from aliphatic Grignard reagents and aryl azides was discussed previously (Eq. 29). The net insertion of a methylene group between the alkyl or aryl group of an organolithium reagent and the nitrogen as part of an animation was also mentioned earlier (Eq. 6). 

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