... 95% confidence limits. MCh6 respectively. These values Approximate values calculated by were obtained using nitrate rather than perchlorate salts. method of Van Uitert and Haas [L. G. Van Uitert and C. G. Haas, THIS JOURNAL, 75,451 (1953)l. noted with alkyl groups in the 2,G positions (com- pounds IV and V). 0 H, B A (13) DF Martin. GA Janusonis and BB Martin, J . Am. Chrm. SOC., 83, 73 (1961). ...