Cyclodehydration of Some 1,n-Diols Catalysed by Sulfated Zirconia
作者:Anil Wali、S. Muthukumaru Pillai
DOI:10.1039/a807189f
日期:——
Sulfated zirconia, a solid acid, is found to be a good catalyst in the cyclodehydration of several diols.
钨酸锆,一种固体酸,被发现是一种在几种二元醇环化脱水反应中很好的催化剂。
Stereoselective Nickel-Catalyzed [2+2+2] Cycloaddition of Enynes and Arynes
作者:Mark Lautens、David Candito
DOI:10.1055/s-0030-1261171
日期:2011.9
Examples of stereoselective reactions of aryne intermediates are rare in the literature. A stereoselectivenickel-catalyzed [2+2+2] cycloaddition of 1,6-enynes with aryne intermediates is reported. Excellent stereoselectivities were observed when a substituent is adjacent to the olefin moiety resulting in trans- stereochemistry in the products. This reaction is capable of generating much complexity
[EN] OXAZOLIDINONE AND / OR ISOXAZOLINE DERIVATIVES AS ANTIBACTERIAL AGENTS<br/>[FR] DERIVES D'OXAZOLIDINONE ET/OU D'ISOXAZOLINE UTILISES COMME AGENTS ANTIBACTERIENS
申请人:ASTRAZENECA AB
公开号:WO2004048392A1
公开(公告)日:2004-06-10
A compound of the formula (I), or a pharmaceutically-acceptable salt, or in-vivo hydrolysable ester thereof: formula (I) wherein in (I) C is for example formula (D), formula (E), formula (H) wherein A and B are independently selected from (i) formula (J) and (ii) formula (K) m is 1 or 2; R2b and R6b, R2a and R6a, R3a and R5a, are for example selected from H, F, OMe and Me; R2b' and R6b', R2a' and R6a', R3a', R5a' are for example selected from H, OMe and Me; R1a is for example optionally substituted (1-10C)alkyl; R1b is for example selected from -NR5C(=W)R4, formula (a) , or formula (b) wherein HET-1 is for example isoxazolyl and HET-2 is for example triazolyl or tetrazolyl. Methods for making compounds of the formula (I), compositions containing them and their use as antibacterial agents are also described.
Tied back: The title reaction was observed when a silicon‐tethered diene was treated with the Hoveyda–Grubbs second‐generation catalyst. The structural requirements for the E‐olefin‐formingring‐closing metathesis, and the transition state leading to E olefin are discussed. This methodology will be useful in the synthesis of polyketides containing a pent‐2‐ene‐1,5‐diol unit.
Pd(II)-catalyzed intramolecularaminocarbonylation of olefins bearing many types of nitrogen nucleophiles has been examined under two typical conditions: acidic conditions [conditions A, typically PdCl(2) (0.1 equiv) and CuCl(2) (3.0 equiv) under 1 atm of CO at room temperature in methanol] and buffered conditions [conditions B, typically PdCl(2) (0.1 equiv) and CuCl(2) (2.3 equiv) under 1 atm of CO at