Chloromethyl with Grignard reagents

A new route to arylsilanes which can be adapted to industrial scale utilizes chloromethyl-disilanes, which are byproducts in the reaction of methyl chloride with silicon. This new method is the most general of those currently available and is compatible with functional groups that cannot be used with Grignard reagents. The reagent required for this route is an acid chloride and substituents that are electron withdrawing increase the rate of the reaction. The general process is shown in equation 15160. 

Benzo[6]thiophene, 2-(aryloxymethyl)-3-chloromethyl-synthesis, 4, 872 Benzo[6]thiophene, 2-arylthio-synthesis, 4, 931 Benzo[6]thiophene, 2-bromo-reaction with potassamide, 4, 829-830 synthesis, 4, 934 Benzo[6]thiophene, 3-bromo-Grignard reagents, 4, 831 reactions, 4, 830 synthesis, 4, 934 Benzo[6]thiophene, 4-bromo-synthesis, 4, 878, 934 Benzo[6]thiophene, 5-bromo-electrophilic substitution, 4, 797 Benzo[6]thiophene, 6-bromo-synthesis, 4, 878, 934 Benzo[6]thiophene, 5-t-buty 1-3-methyl-synthesis, 4, 880... 

The enantiomerically pure chloromethyl complexes (-)-(/ )-9 and ( + )-(S)-9 (shown below as 10) can be converted to iron-alkyl complexes by treatment with sodium borohydride, Grignard reagents, or alkyllithium species, with no loss of enantiomeric purity16,17 (see also Houben-Weyl, Vol. 13/9 a, p 193). 

TrimcthylsUylmcthylmagncsiiun chloride, (CH3)3SiCH2MgCl (1). Mol. wt. 146.99. The Grignard reagent is prepared in the usual way by reaction of magnesium with chloromethyl(trimethyl)silane.1... 

Thiophene, 2-hydroxy-5-methyl-synthesis, 4, 926 Thiophene, iodo-Grignard reagents, 4, 79, 831 photolysis, 4, 832 reactions, 4, 932 with phenyllithium, 4, 831 synthesis, 4, 835, 934 Ullmann coupling reactions, 4, 837 Thiophene, 2-isopropyl-3-methyl-synthesis, 4, 901 Thiophene, mercapto-reactions, 4, 78 stability, 4, 825 synthesis, 4, 80, 835, 930-931 tautomerism, 4, 38, 727 Thiophene, 2-mercapto-5-methylthio-synthesis, 4, 872 Thiophene, 2-methoxy-chloromethylation, 4, 759 Thiophene, 3-methoxy-chloromethylation, 4, 759 Thiophene, 5-methoxy-2,4-dinitro-Meisenheimer complexes, 4, 815 Thiophene, 2-methoxy-5-methyl-Vilsmeier formylation, 4, 759-760 Thiophene, 2-methoxy-3-nitro-reactions, 4, 827 Thiophene, 2-methyl-bromination, 4, 799-800 conformation, 4, 32 HNMR, 4, 730 metallation, 4, 773 synthesis, 4, 885, 887 trifluoroacetylation, 4, 751 Thiophene, 3-methyl-bromination, 4, 799-800 conformation, 4, 32 H NMR, 4, 730 metallation, 4, 60 oxidation, 4, 800... 

Chloromethyl-5,6-dihydro- 1,3-oxazines react with aryl Grignard reagents, giving ultimately an arylacetic acid.249 Quaternary salts of 5,6-dihydro compounds also furnish carboxylic acids.240... 

Add 2-chloromethyl-2-propenyl benzyl ether3,42 (0.49 g, 2.5 mmol) and 1,2-dibromoethane (0.094 g, 0.5 mmol), and regulate the reaction temperature so as to induce and maintain a smooth reaction of the chloride with magnesium producing the desired Grignard reagent (about 90% yield). 

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