Part 1. B-ferrocenylalkyl carbonium ions. Part 2. The stereospecific syntheses of the exo and endo isomers of a-hydroxymethyl-1,2-tetramethyleneferrocene

Part I The solvolysis mechanism of [Beta]-ferrocenylalkyl tosylates is discussed. Evidence is presented which shows that solvolysis occurs with preferential participation of the interannular electrons of the ferrocene moiety leading to intermediate formation of very stable carbonium ions. The products resulting from these solvolysis reactions demonstrate that these carbonium ions exhibit features expected for both ferrocenyl ring-bridged and iron-stabilized intermediates. The stereochemistry of solvolysis of (-)-1-ferrocenyl-2propyl-p-toluenesulfonate has also been examined and found to occur with complete retention of configuration. Part II The stereospecific syntheses of the exo and endo isomers of [alpha]-hydroxymethyl-1,2-tetramethyleneferrocene is described.