Functional alkyne groups

The extent of acetylene insertion can be limited by the control of reaction conditions, such as the ratio of reactant acetylene to the number of Si-Si bonds or reaction time. In addition, if an organic substrate with two alkyne functional groups is used, cross-linked polymers are formed. Other palla-... 

In them the functional group is (-C = C-). The alkyne functional group consists of a carbon carbon triple bond and is linear in shape with bond angles of 180 (Following fig.). 

Labadie, G.R., Wiswanathan, R., and Poulter, CD. (2007). Farnesyl diphosphate analogues with 6-bioorthogonal azide and alkyne functional groups for protein farnesyl transferase-catalyzed ligation reactions. J Org Chem 72 9291-9297. 

Several non-natural a2,6-linked sialosides 36-40 with azide or alkyne-modified sialic acid residues were also prepared in excellent yields (86%-93%) from their C2- or C6- modified ManNAc or mannose bearing corresponding azide or alkyne functional groups 30-34 using the one-pot three-enzyme approach and GaipOMe (35) as an acceptor for Pd2,6ST (Scheme 5). 

A few drugs contain alkyne functional groups, but they are not naturally occurring compounds. They exist only because chemists have been able to synthesize them. Their trade names are shown in green. Trade names are always capitalized and can be used for commercial purposes only by the owner of the registered trademark (Section 30.1). 

If the same number for the alkyne functional group suffix is obtained counting from either direction along the carbon chain, the correct systematic name is the one that contains the lowest substituent number. If the compound contains more than one substituent, the substituents are listed in alphabetical order. 

In addition to the reviews mentioned above, a short review, in Japanese, has also been published. Since 1978 many new processes involving compounds within which there is an alkyne functional group have been published. 

If the substrate contains both azide and alkyne functional groups, intramolecular and intermolecular cycloaddition reactions are possible. While the former... 

Alkene metathesis catalysts are also capable of undergoing reaction with aUene and alkyne functionality, which can lead to the synthesis of polyene compounds. For example. Diver has explored the use of alkene/alkyne CM, which leads to 2-substituted 1,3-dienes (Scheme 2.11). Prunet has recently disclosed an elegant metathesis cascade sequence towards the synthesis of Taxol, involving two alkenes and one alkyne functional group (Scheme 2.12) the desired product was accompanied by small quantities of a side product that resulted from metathesis of the two alkenes. 

The four compounds shown next are synthetic steroids that are used for birth control each contains an alkyne functional group. Most birth control pills contain ethinyl estradiol (a compound structurally similar to estradiol) and a compound structurally similar to progesterone (such as norethindrone). Ethinyl estradiol prevents ovulation, whereas norethindrone makes it difficult for a fertilized egg to attach to the wall of the uterus. 

Mifepristone and levonorgestrel are also synthetic steroids that contain an alkyne functional group. Mifepristone, also known as RU-486, induces an abortion if taken early in pregnancy. Its name comes from Roussel-Uclaf, the French pharmaceutical company where it was first synthesized, and from an arbitrary lab serial number. Levonorgestrel is an emergency contraceptive pill. It prevents pregnancy if taken within a few days of conception. 

In a similar way, Stenzel and coworkers (Chen et al., 2009) recently synthesized dendrimers by successive thiol-yne chemistry and esterification reactions. As for the thiol-ene case, it is an efficient process and does not require a metal catalyst. For the thiol-yne system, the reaction proceeds by reacting two equivalents of thiol with the alkyne, via a two-step process. Therefore, after the reaction, each alkyne functional group will be combined with two thiols, which is very attractive and advantageous in the synthesis of dendrimers. 

Alkyne Functional Group, -C=C-Alkyne C=C Stretching Vibrations Alkyne C-H Vibrations Alkyne Skeletal Vibrations Nitriles, -C=N Isonitriles, -N=C Nitrile N-oxides, -C=N O ... 

The Huisgen cycloaddition reaction of azides with alkynes to produce triazoles was used to produce HA hydrogels and to encapsulate yeast cells during crosslinking. In this method, azide and alkyne functional groups were installed on HA using EDC chemistry. The hydrogel... 

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