ortho-directed lithiation of omega-phenoxyalkanethiols and N,N-dimethyl-omega-phenoxyalkylamines. Crystal structure of bis[o-[(2-dimethylamino)ethoxy]phenyl]-mercury

omega-Phenoxyalkanethiols, PhO(CH2)(n)SH (n = 2 - 6) were prepared and orth o-metallated with two equivalents of n-butyllithium in tetrahydrofuran/meth ylcyclohexane. Carboxylation and subsequent acidic hydrolysis of the result ing dilithiated species yielded the corresponding o-(omega-mercaptoalkoxy)b enzoic acids in yields ranging from 30 to 78%. The previously reported meth odology for the ortho-lithiation of (2-dimethylamino)ethoxy-benzene by n-bu tyllithium in ether was extended to higher members of this class, PhO(CH2)( n)NMe2 with n = 2 - 4. The resulting organolithiums react normally with ele ctrophilic reagents, benzaldehyde (n = 2 - 4), benzophenone (n = 2 - 4) and dichlorodiphenysilane (n = 2) in yields of 63 - 77%; in addition, reaction with 0.5 molar equiv of mercuric dichloride (n = 2) afforded the bis[o-[(2 -dimethylamino)ethoxy]phenyl]mercury in a 78% yield, the crystal structure of which has been determined.