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The nerve gas agent sarin, containing both C–P and F–P bonds, is a phosphonate. [citation needed] Phosphinates feature two P–C bonds, with the general formula R 2 P(=O)(OR'). A commercially significant member is the herbicide glufosinate. Similar to glyphosate mentioned above, it has the structure CH 3 P(O)(OH)CH 2 CH 2 CH(NH 2)CO 2 H.
The figure below illustrates one of the commonly accepted models for stereoselection without any modification to the Henry reaction. In this model, stereoselectivity is governed by the size of the R groups in the model (such as a carbon chain), as well as by a transition state that minimizes dipole by orienting the nitro group and carbonyl oxygen anti each other (on opposite sides of the ...
P-persistent This approach lies between the 1-persistent and non-persistent CSMA access modes. [1] When the transmitting node is ready to transmit data, it senses the transmission medium for idle or busy. If idle, then it transmits immediately. If busy, then it senses the transmission medium continuously until it becomes idle, then transmits ...
Others, however, insist that such a usage is an abuse of terminology, and limit the Michael addition to the formation of carbon–carbon bonds through the addition of carbon nucleophiles. The terms oxa-Michael reaction and aza-Michael reaction [ 2 ] have been used to refer to the 1,4-addition of oxygen and nitrogen nucleophiles, respectively.
The rarity of C-C activation processes has been attributed to Steric effects that protect C-C bonds. Furthermore, the directionality of C-C bonds as compared to C-H bonds makes orbital interaction with transition metals less favorable. [2] Thermodynamically, C-C bond activation is more favored than C-H bond activation as the strength of a ...
After the active form of the ruthenium catalyst complex is generated from 1, acetophenone coordinates to the complex via its carbonyl oxygen and agostically via its ortho C-H bond (2). As in the Ru 0 proposed mechanism, this agostic interaction leads to the oxidative addition of the ortho C-H. Reductive elimination releases H 2 , which remains ...
The Negishi coupling finds common use in the field of total synthesis as a method for selectively forming C-C bonds between complex synthetic intermediates. The reaction allows for the coupling of sp 3 , sp 2 , and sp carbon atoms, (see orbital hybridization ) which make it somewhat unusual among the palladium-catalyzed coupling reactions .
The value of 1 J 13 C-1 H for cyclopropane, cyclobutane and cyclopentane are 161, 134, and 128 Hz, respectively. This is a consequence of the fact that the C-C bonds in small, strained rings (cyclopropane and cyclobutane) employ excess p character to accommodate their molecular geometries (these bonds are famously known as 'banana bonds'). In ...