title: A practical synthesis of isomerically pure 1,10-difunctionalized derivatives of the [closo-1-CB9H10] anion.
abstract: The isomer-free [closo-1-CB9H(8)-1-COOH-10-I]- anion was prepared in four steps and 10% overall yield from B10H14. The key step is the skeletal isomerization of the [closo-2-CB9H8-2-COOH-7-I]- anion to a mixture of the 10- and 6-iodo derivatives of [closo-1-CB9H(9)-1-COOH]- formed in up to a 3:1 ratio. The carboxylic acid 4 was converted to the amine [closo-1-CB9H(8)-1-NH(2)-10-I]- using the Curtius reaction. The relative thermodynamic stability of each product was calculated at the DFT and MP2 levels of theory. The regioselectivity of electrophilic substitution in [closo-CB9H10]- derivatives was briefly investigated using the NBO population analysis of the MP2 wave function.
authors.affiliation: Organic Materials Research Group, Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA.
authors.forename: Bryan
authors.initials: B
authors.lastname: Ringstrand
authors.forename: Andrzej
authors.initials: A
authors.lastname: Balinski
authors.forename: Andreas
authors.initials: A
authors.lastname: Franken
authors.forename: Piotr
authors.initials: P
authors.lastname: Kaszynski