Terminal alkynes as a position abstraction tool for the preparation of nano materials

Abstract

The terminal alkyne residue, -CequivC . H is one of the most acidic among the C-H groups (Pedireddy & Desiraju,1992). The ethynyl or propargyl radical formed by removing the terminal hydrogen in an alkyne is likely to have more affinity for hydrogen. It can be used for removing the hydrogen atoms at desired places from diamondoid structures in molecular manufacturing. Hence the terminal alkynes can be used as position abstraction tool for hydrogen in the production of nano materials (Musgrave et.al. 1991). The radical of a molecule having the ethynyl or propargyl group at the end can be embedded into structures that can act like the base of a handle. This arrangement can act as an excellent tool tip. Hydrogen bonding plays an important role in deciding the suitability of a terminal alkyne to act as a tool tip molecule. An analysis of the crystallographic and spectrosc opic data help us gain an insight into C-H...X hydrogen bond interactions (Desiraju 1991, Steiner 2003). The single crystal X ray diffraction studies reveal the three dimensional view of the molecule and provide the inter molecular C ... O distances. Infrared (IR) spectroscopy has a prominent place in the history of investigation of hydrogen bonding (Mootz and Deeg 1992). The choice of terminal acetelenes to act as a tool tip molecule can be made by taking into consideration the evidence obtained from crystallographic and spectroscopic data. The crystallographic (Lakshmi et al, 1996) and spectroscopic data of 7beta hydroxy -7alpha-(3-propargyl)-3-methyl-spiro[5.5]undec- 2-en-l-one are analysed.