Search results
Results from the WOW.Com Content Network
A nitrogen bound to both a good electrofuge and a good nucleofuge is known as a nitrenoid (for its resemblance to a nitrene). [2] Nitrenes lack a full octet of electrons are thus highly electrophilic; nitrenoids exhibit analogous behavior and are often good substrates for electrophilic amination reactions.
A carbon–nitrogen bond is a covalent bond between carbon and nitrogen and is one of the most abundant bonds in organic chemistry and biochemistry. [ 1 ] Nitrogen has five valence electrons and in simple amines it is trivalent , with the two remaining electrons forming a lone pair .
A wide variety of carbohydrates, as well as nitrogen nucleophiles (ex. amino acids), can be used to furnish highly stereochemically enriched products. The aminopolyol products can then undergo further reactions to prepare aminosugars. Petasis used this reaction to prepare Boc-protected mannosamine from D-arabinose. [19]
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 ...
This free-energy relationship relates the pseudo first order reaction rate constant (in water at 25 °C), k, of a reaction, normalized to the reaction rate, k 0, of a standard reaction with water as the nucleophile, to a nucleophilic constant n for a given nucleophile and a substrate constant s that depends on the sensitivity of a substrate to ...
In today's puzzle, there are six theme words to find (including the spangram). Hint: The first one can be found in the top-half of the board. Here are the first two letters for each word:
Similarly, an interaction of an oxygen lone pair with σ* C-C orbital should be responsible for the lengthened C1-C2 bond [152.75(15) pm] compared to the average C sp2-C sp2 bonds which are 151.3 pm. Also, the C1-C11 bond [152.16(17) pm] is slightly shorter than the average C sp3-C sp3 bond which is around 153.0 pm. Carbinol tetrahedral ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!