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Legumes are simultaneously one of the largest families of crop plants and a cornerstone in the biological nitrogen cycle. We combined molecular and phylogenetic analyses to evaluate genome conservation both within and between the two major clades of crop legumes. Genetic mapping of orthologous genes identifies broad conservation of genome macrostructure, especially within the galegoid legumes, while also highlighting inferred chromosomal rearrangements that may underlie the variation in chromosome number between these species. As a complement to comparative genetic mapping, we compared sequenced regions of the model legume Medicago truncatula with those of the diploid Lotus japonicus and the polyploid Glycine max. High conservation was observed between the genomes of M. truncatula and L. japonicus, whereas lower levels of conservation were evident between M. truncatula and G. max. In all cases, conserved genome microstructure was punctuated by significant structural divergence, including frequent insertion/deletion of individual genes or groups of genes and lineage-specific expansion/contraction of gene families. These results suggest that comparative mapping may have considerable utility for basic and applied research in the legumes, although its predictive value is likely to be tempered by phylogenetic distance and genome duplication.

Aryl bromides bearing a potassium trifluoroborate moiety were subjected to lithium-halogen exchange at low temperatures using a variety of alkyllithium reagents. Potassium trifluoroborates afforded good to excellent yields of the corresponding alcohols when aldehydes or ketones were used as the electrophilic partner.

A uniquely stable acyl potassium trifluoroborate, potassium (2-phenylacetyl)trifluoroborate, is prepared and isolated. The reagent has reacted with azides to form amides in the presence of an activating Lewis acid.

The development of a mild and general method for the synthesis of cis-alkenyl pinacolboronates and potassium organotrifluoroborates with corresponding terminal alkynes as starting material is reported. The alkynyl pinacolboronates bearing various functional groups are stereoseletively reduced to the cis-alkenyl pinacolboronates via hydroboration with dicyclohexylborane.