Butyl Magnesium

C4H, MgBr + HCOOCaHs (C H.ajaCHOMgBr + CjHjOMgBr n-Butyl magnesium bromide Ethyl formate... 

To a mixture of 0.10 mol of 1-ethoxy-l,2-heptadiene (see this chapter, Exp. 13) and 120 ml of diethyl ether was added 1 g of copper(I) bromide. A solution of butyl magnesium bromide in about 200 ml of diethyl ether, prepared from 0.25 mol of butyl bromide (see Chapter II, Exp. 5) was added in 15 min. The reaction was weakly exothermic and the temperature rose slowly to about 32°C. The mixture was held for an additional 40 min at that temperature, then the black reaction mixture was... 

In some instances a carbon-carbon bond can be formed with C-nucleophiles. For example, 3-carboxamido-6-methylpyridazine is produced from 3-iodo-6-methylpyridazine by treatment with potassium cyanide in aqueous ethanol and l,3-dimethyl-6-oxo-l,6-dihydro-pyridazine-4-carboxylic acid from 4-chloro-l,3-dimethylpyridazin-6-(lH)-one by reaction with a mixture of cuprous chloride and potassium cyanide. Chloro-substituted pyridazines react with Grignard reagents. For example, 3,4,6-trichloropyridazine reacts with f-butyl-magnesium chloride to give 4-t-butyl-3,5,6-trichloro-l,4-dihydropyridazine (120) and 4,5-di-t-butyl-3,6-dichloro-l,4-dihydropyridazine (121) and both are converted into 4-t-butyl-3,6-dichloropyridazine (122 Scheme 38). 

The first reaction appears to consist of the formation of an oxonium addition product of the ethylene oxide and the butyl-magnesium bromide. 

Neopentyl alcohol has been made by lithium aluminum hydride reduction of trimethylacetic acid and by treating ferf-butyl-magnesium chloride with methyl formate. ... 

The 1 -phenyl-pentanol-(1) may be prepared in any convenient manner. Benzaldehyde may be reacted with n-butyl-magnesium bromide, and after purification 1-phenyl-pentanol-(1) Is obtained in the form of a colorless oil at room temperature. 

The products in such cases contain complexes between M-butyl-magnesium chloride and the particular alkoxide employed. With the stated Low proportions of alkoxides, these complexes broadly resemble the alkoxide-free materials, but increased proportions of the alkoxide component give complexes having generally decreased chemical reactivity (see references 3 and 4). 

The directions given in Exp. XXX by the reaction of tert-butyl magnesium chloride and carbon dioxide are an improvement on those described by Bouveault.9... 

Sulfinylacetamide anions, e.g., ( + )-(/J)-AfAr-dimethyl-2-(4-methylphenylsulfinyl)acctamide, when generated with fe/V-butyl magnesium bromide, also react with aldehydes to give aldol products with a high degree of stereoselectivity42,43. 

Alternatively, use the equivalent amount of n-butyl chloride and prepare the Grignard reagent as for sec.-butyl magnesium chloride. 

As expected, other enol ethers work well in these procedures. For example, Jones and Selenski find that implementation of method F, which occurs by addition of MeMgBr to benzaldehyde 5 in the presence of dihydropyran (DHP) at 78 °C affords a 66% yield of the corresponding tricyclic ketal 59 with better than 50 1 endo diastereoselectivity (Fig. 4.31).27 On the contrary, Lindsey reports use of method H with the benzyl alcohol 35 and diethylketene acetal. The cycloaddition reaction occurs almost instantaneously upon deprotonation of the benzyl alcohol 35 by f-butyl-magnesium bromide in the presence of the ketene acetal and yields the corresponding benzopyran ortho ester 60 in a 67% yield.29... 

Yaodong Huang, while pursuing the synthesis of ( + )-berkelic acid (69), reported a diastereoselective cycloaddition using method H that leads to another type of 5,6-aryloxy spiroketals (Fig. 4.36).32 For example, addition of three equivalents of t-butyl magnesium bromide to alcohol 70 in the presence of the exocyclic enol ether 71 proceeds in a 72% yield to the spiroketal 72 with a 4.5 1 selectivity favoring the endo approach (Fig. 4.36). Additional experiments suggest the bromine atom decreases the HOMO-LUMO band gap and improves diastereoselectivity. 

One surprising example is how ferric (not ferrous) chloride catalyzes the formation of ketyl radicals in a Gringnard-type reaction between ( 113)3001, Mg, and (0Hj)20=O (Ashby and Wiese-mann 1978). The initially formed tert-butyl magnesium chloride reacts with ferric chloride and gives tert-butyl iron(Ill) dichloride ... 

Similar yields can be obtained in this silylation by using the chloromagnesium salt (from butyl magnesium chloride) as described in Org. Synth. 1987, 6S, 61. 

The reaction of 1-phenylethyl-, 2-octyl-, and 2-butyl-magnesium chloride (36a, b, c) with vinyl bromide (37a), (E)-p-bromostyrene (37b), 2-bromopropene (37c), and bromobenzene (37d) was carried out in the presence of 0.5 mol- % of a nickel catalyst prepared in situ from nickel chloride and the chiral ligand (35). 

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