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 Rainforest The tropical rainforest is a hot, moist biome found near Earth's equator. The world's largest tropical rainforests are in South America, Africa, and Southeast Asia. Tropical rainforests receive from 60 to 160 inches of precipitation that is fairly evenly distributed throughout the year.