A mild, convenient protocol for the synthesis of cis-aziridines employs a catalytic amount of Brnsted acid. Diazo compound decomposition via alkylation or homocoupling upon exposure to a proton source is slow relative to [2 + 1] annulation in the presence of a Schiff base. A. L. Williams, J. N. Johnston, J. Am. Chem.
The tropical savanna is a biome characterized by tall grasses and occasional trees. Large regions of tropical savanna extend through the nations of Botswana, Namibia, and Kenya in Africa, southern Brazil, India, and Australia. Surprisingly, the Everglades of southern Florida in North America is also a tropical savanna. Photo  2000-www.arttoday.com.
Tropical plants are popular because they are often visually interesting and showy. Although they only grow outdoors in warm climates, many tropical plants grow very well as houseplants in cooler climates. Popular tropical houseplants include both flowering and leafy plants. In some cases, people grow potted tropical trees as indoor houseplants.