NMR investigations on Stannabicycloundecanes of the type RSn(CH2CH2CH2)3N

The 1H, 13C, and 119Sn NMR data of seven stannabicycloundecanes of the type RSn(CH2CH2CH2)3N (1, R = Cl; 2, R = Br; 3, R = I; 4, R = OH; 5, R = SPh; 6, R = Me; 7, R = Sn(CH2CH2CH2)3N) are reported. From 1H NMR coalescence data at low temperature the free activation enthalpies for the racemisation of the bicyclo[3.3.3]skeleton were estimated to be 37 ± 1 kJ/mol. They are independent of the substituent R. However, it decreases when the tin atom is replaced by silicon for R = Me. NMR‐Untersuchungen an Stannabicycloundecanen des Typs RSn(CH2CH2CH2)3N Es werden 1H‐, 13C‐ und 119Sn‐NMR‐Daten von sieben Stannabicycloundecanen des Typs RSn(CH2CH2CH2)3N (1, R = Cl; 2, R = Br; 3, R = I; 4, R = OH; 5, R = SPh; 6, R = Me; 7, R = Sn(CH2CH2CH2)3N) mitgeteilt. Aus den Protonen‐NMR‐Koaleszenzdaten bei tiefer Temperatur wird ΔG Tc* für die Racemisierung des Bicyclo[3.3.3]‐Gerüstes zu 37 ± 1 kJ/mol bestimmt. Die Werte sind unabhängig vom Substituenten R. In den entsprechenden Siliciumderivaten (R = Me) werden geringere Aktivierungsparameter gefunden.