Theoretical Studies and Physical Measurements

Theoretical Studies and Physical Measurements.—K sector rule for chiral allenes has been derived which relates the position of the substituent to the sign of the lowest-energy Cotton effect. A physical basis is proposed for the Lowe-Brewster rule relating the configuration of a chiral allene to the sign of its D-line rotation. Calculations have been made on the addition of allene and acetylene to vinyl cations via concerted and non-concerted pathways. The precedence for groups in the allenic diphenylphosphine (380) for eclipsing with the allenyl system have been studied by n.m.r. C N.m.r. 

The vapour-phase infrared spectrum and structure of fulvenallene have been determined and hydrogen-bonding between phenol and acetylene or allene derivatives has bron studied using the hydroxyl stretching band. The basicity of acetylenes is greater than that of allenes and olefins which are of the same order of magnitude.  

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