Miscellaneous preparations

Most of the following methods represent less general preparative routes to enamines. In some examples the enamines produced can be obtained via methods already described in preceding sections, while in other examples the enamines produced are uniquely synthesized. In an attempt to present these miscellaneous preparations in other than a random order, they have been divided into reactions involving alkylations (A) and others (B). 

l-(l-Cyclopenten-l-yl)piperidine (148) reaeted with N-methyl-3-bromopropylamine hydrobromide to yield 74% of a mixture of enamines (149) 112). The proposed mechanism involved an amine exchange to give the enamine 150 which underwent internal alkylation. 

Displacement of Vinyl fluorine or chloride by secondary amines has given some unusual enamines as illustrated for the preparation of 1,1-difluoro-2-piperidino-3-phenyl-2-cyclobutene (151) (US), l,l-difluoro-2,4-dipiperidino-3-phenyl-2-cyclobutene (152) (114), and 2-phenyl-3-(l -aziridinyl)-2-cyclohexenone (153) (115). 

N-(2-Bromoallyl)-ethylamine with sodium amide in liquid ammonia gave N-ethylallenimine (154) by either of the paths shown (116,117). 

Fulvene-type enamines, which possess some nonbenzenoid aromatic character, have been synthesized by treating cyclopentadienylsodium with an amide-dimethyl sulfate eomplex (117aJ17b) or quaternary pyridinium salts (117c). One of the simplest ones produced is 6-(dimethylamino)fulvene (117a,117d). 

Zabicky, J. The Chemistry of Amides John Wiley Sons Ltd London, 1970. 

Bethmont, V. Jacquot, L. Lemaire, M. Red. Trav. Chim. Pays-Bas 1996,115, 231-238. 

Fuchigami, T. Electrochemistry of organosilicon compounds. In Rappoport, Z., Apeloig, Y., Eds. Wiley Chichester, 1998 pp 1187—1232. 

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Miscellaneous Preparations. Many laboratory innovations have been mn. 

Various types of preparations are used for the treatment of otic (ear) disorders. Otic preparations can be divided into three categories (1) antibiotics (2) antibiotic and steroid combinations and (3) miscellaneous preparations. The miscellaneous preparations usually contain one or more of the following ingredients ... 

Miscellaneous Preparations of Acetylenic Deri vatives 1. Halogen Compounds, Sulfinates, Sulfonates and Acetates All temperatures are internal, unless indicated otherwise... 

A method for the isomerization of trans dimeric compounds to cis dimeric isomers is indicated in Section 5, Miscellaneous Preparation 11 [71]. 

Preparation of Sulfonamides and Sulfinamides 249 Table 8.8. Miscellaneous preparations of sulfonamides from sulfonyl chlorides and from sulfinamides. 

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