CONTRIBUTIONS TO THE CHEMISTRY OF BORON, 242 - REARRANGEMENT OF BIS(DIMETHYLAMINO)BIS(1-INDENYL)DIBORANE(4) INTO BIS(DIMETHYLAMINO)BIS(3-INDENYL)DIBORANE(4)

Indenylithium reacts with dichlorobis(dimethylamino)diborane(4) with f ormation of bis(dimethylamino)bis(1-indenyl)-diborane(4) which rearran ges on heating to the isomer bis(dimethylamino)bis(3-indenyl)diborane( 4). The ''mixed'' is(dimethylamino)(1-indenyl)(3-indenyl)diborane(4) i s obtained from indenyllithium and chlorobis(dimethylamino)(3-indenyl) diborane(4). The main structural differences between the two isomers 3 and 4 are a sightly shorter B-B bond in 4, as well as a stronger twis t about the B-B (89.9 degrees vs. 67.4 degrees) and, as expected, a sh orter B-C bond. There is, however, no significant B-C pi bonding.