In acidic aqueous solution, oxidation of the β-amino alcohols [Formula: see text], I, and [Formula: see text], II, (R = H, alkyl) using the Ti(III)–H2O2 flow technique gave the radicals [Formula: see text], and [Formula: see text]. The spectrum of [Formula: see text] shows restricted rotation about the C1—C2 bond assigned to intramolecular hydrogen bonding.Under neutral conditions, oxidation of I gave the spectrum of •CH2CHO, and of II the acetonyl radical •CH2COCH3. It is proposed that elimination occurs by deprotonation of the abstraction radical in a hydrogen-bonded conformation, followed by rapid fragmentation to yield the α-carbonyl radical.

A Bacillus sp. capable of utilizing phosphite and hypophosphite under anaerobic conditions was isolated from Cape Canaveral soil samples. The organism was isolated on a glucose-mineral salts medium with phosphate deleted. Anaerobic cultivation of this isolate resulted in decreases in the hypophosphite or phosphite concentration, increases in turbidity, cell count, and dry-cell weight, and decreases in pH and glucose concentration. The optimum hypophosphite concentration for this isolate was 60 Ag/ml, whereas the optimum phosphate concentration was greater than 1,000 ,.g/ml, suggesting that higher concentrations of hypophosphite may be toxic to this isolate. Hypophosphite or phosphite utilization was accompanied by little or no detectable accumulation of phosphate in the medium, and 32P-labeled hypophosphite was incorporated into the cell as organic phosphate. When phosphate was present in the medium, the isolate failed to metabolize phosphite. In the presence of phosphite and hypophosphite, the isolate first utilized phosphite and then hypophosphite.

2,6-Di-t-butylbenzoquinone can interact with group IVB organometallic compounds to give the stable substituted phenoxyl radicals detectable by e.s.r. The strong bonding between silicon and oxygen atoms together with the unusual stability of the resulting phenoxyl radicals show that 2,6-di-t-butylbenzoquinone is an excellent spin trap of organosilyl radicals. This quinone has also been used successfully to trap both diphenylphosphino and phenylthiyl radicals.

Electron spin resonance spectra of tertiary α-carbonyl radicals, R1R2ĊCOR3 (R1R2R3 = H, alkyl), at 24 °C in aqueous solution show fully restricted rotation about the Ċ—CO bond. The effect is identified by differing h.f.s. constants for equivalent substituents R1 and R2. The radical intermediates are generated by direct abstraction, radical fragmentation, and reductive elimination processes.

The photoreduction of 2-tert-butyl-p-benzoquinone and 2,5- and 2,6-di-tert-butyl-p-benzoquinone were studied by esr spectroscopy. In the photolysis of 2,6-di-tert-butyl-p-benzoquinone, only one semiquinone radical was observed and its decay kinetics were monitored by esr. The reduction of the triplet 2-tert-butyl-p-benzoqinone leads to the formation of isomeric semiquinone radicals 1 and 2 in the primary photochemical processes, and this is then followed by a chemical equilibrium between the two isomeric radicals. The relative rates of formation of the two radicals cannot be monitored by conventional esr methods but the CIDEP results show that the formation of radical 2 is about five to seven times faster than that of radical 1. A secondary reaction of the phenoxy radical with a product benzohydrofuran 4 leads to the observation of a polarized radical 3 which derives all its polarization from the primary phenoxy radical.