A number df phosphorus-containing esters were made from 2,2-dimethyl-l,3-propanediol. Phosphoryl chloride gave a cyclic phosphorochloridate which could be treated with an alcohol or phenol to produce a neutral ester. Phosphonic dichlorides gave cyclic neutral esters directly. When phosphorus trichloride was used, a cyclic bisphosphite was produced; howcver, when this reaction was carried out in the presence of an alcohol, a cyclic hydrogen phosphite was formed. Treatment of 2,2-dimethyl-1,3-propanediol with diethyl phosphorochloridate gave a neutral bisphosphate which on pyrolysis liberated triethyl phosphate to yield a cyclic neutral ester. In general, these derivatives of 2,2-dimethyl-l13-propanediol are stable, white, crystalline compounds.This investigation was undertaken to study the preparation and properties of phosphorus-containing esters derived from 2,2-dimethyl-l,3-propanediol, a derivative of isobutyraldehyde. These esters glycol with a phosphorus dihalide or trihalide usually result,s in the formation of cyclic esters.'-la (1) A.

Tolerance of corn (Zea mays L.) to low temperature conditions after planting requires rapid germination, vigorous seedling growth, and resistance to disease and insect pests. A selection scheme designed to improve cold tolerance in breeding material was initiated in two breeding populations, Iowa Stiff Stalk Synthetic (SSCG) and Pioneer Cold Tolerant Synthetic (CTCG). Laboratory and field selection were employed in the procedure. Seedlings developed from the first seeds to germinate at 7.2 C in the laboratory (20% selected) were transplanted to the field, selected for agronomic traits, and self‐pollinated. The selfed progenies were recombined in winter nurseries to initiate the next cycle of selection in the laboratory.Regression analyses of the four cycles of selection indicated that cold germination under laboratory conditions (7.2 C) improved 8.8 and 9.9% per cycle in CTCG and SSCG, respectively. In the field, however, little improvement was observed in emergence or seedling vigor. The lack of correlation between laboratory and field results for these cold‐tolerant traits was attributed to mild spring weather during the 2 years of evaluation. Selection for germination at cold temperatures did not have any detrimental effects on other agronomic traits measured in the populations.

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To learn more about early season growth of corn (Zea mays L.), generation means analyses were used to study inheritance of germination at 7.2 C in the laboratory, and emergence, juvenile growth, and yield in the field. Six inbred parents, their 15 F1 hybrids, their 15 F2, and their 30 backcross populations were used in the analyses. The inbreds were classified into warm (W) and cool (C) season groups based upon their reaction to cold and heat stress in previous experiments.For the specific group of parents evaluated, generation means analyses indicated that epistatic gene effects as well as additive and dominance gene effects contributed significantly to the variation observed for germination at 7.2 C in the laboratory and for emergence measured in the field. Seedling vigor or growth after emergence in the field appeared to be conditioned predominantly by additive and dominance gene effects. Although some epistatic gene effects were detected, grain yield in the specific group of parents studied was controlled by additive and dominance gene effects.Contrary to expectations, C ✕ C crosses were no better than W ✕ W or C ✕ W crosses for the cold tolerance traits studied. Percent germination and field emergence data favored W ✕ W crosses, while C ✕ C crosses were slightly better for early season vigor. W ✕ W crosses produced the highest grain yield followed by C ✕ W and C ✕ C crosses.

Ethyl 8-fluoro-3-oxooctanoate was prepared from 6fluorohexanoyl chloride4 (7.6 g., 0.05 mole) in the same way. Distillation of the residue after solvent removal gave the ester, b.p. 106-114°(2-3 mm.). This was purified by being dissolved in petroleum ether and washed once with 10% sodium bicarbonate (10 ml.). This volume of sodium bicarbonate should not be exceeded, since the water-soluble sodium salt of the enol form of the ketoester is readily formed and remains in the aqueous phase. After washing with water, ethylene chloride was added to the organic layer, and the solvents were removed under reduced pressure. The residue on fractionation yielded ethyl 8-fluoro-3-oxooctanoate (5 g., 49%) of b.p. 107°(3 mm.) and n25d 1.4223.