A series of bromo-substituted allyl-and diallyl-substituted sulfonamides have been found to undergo free radical cyclization when treated with tri-rc-butyltin hydride in the presence of AIBN. The regiochemical course of the cyclization depends on the nature of the substituent groups attached to the ir-bond. The stereoelectronic factors governing the cyclization reaction of these JV-allylsulfonamides are even more stringent than those which occur with the simple 5-hexenyl system. This is probably related to the shorter C-N bond distance which promotes the 5-exo trig cyclization pathway. The present method provides an attractive entry to the preparation of pyrrolidines from easily available N-(2-bromoethyl)-A-allyl-and N-(2-bromopropenyl) -IV-allylsulfonamides. The method represents a clear-cut example of the use of hetero-substituted radicals in C-C bond-forming processes.

A series of -cyanoaminosilanes have been found to act as azomethine ylide equivalents. Treatment of these compounds with silver fluoride in the presence of electron-deficient alkynes and olefins gives substituted pyrroles and pyrrolidines in high yield. It was found that A-benzyl-TV-(cyanomethyl) -N-[ (trimethylsilyl)methyl] amine undergoes stereospecific cycloaddition with dimethyl fumarate and maléate. The stereospecificity of the reaction is consistent with a concerted cycloaddition reaction. The cycloaddition behavior of an unsymmetrically substituted -cyanosilylamine with methyl propicíate was also examined and found to react with high overall regioselectivity.The synthetic utility of cyanoaminosilanes as azomethine ylide equivalents was demonstrated by the preparation of a Reniera isoindole alkaloid. The key step in the synthesis involved the reaction of 2-methyl-3-methoxyquinone with iV-methyl-Ai-(cyanomethyl)-iV-[(trimethylsilyl)methyl]amine in the presence of silver fluoride to give 2,5dimethyl-6-methoxy-2H-isoindole-4,7-dione in good yield.

Women are still underrepresented in the so-called "hard" fields of science, technology,e ngineering, and mathematics( STEM). One fact observed is that they step out of the field of study after university while men are more likely to stay in STEM.A s ac onsequence, women are also underrepresentedi nS TEM-related industrial or academic leading positions and boards. In addition to the tendency to leaveresearch earlier than similarly qualified men, women in science are still paidl ess, promoted less, and win fewer grants.A ccording to a2 006 study,t he genderp ay gap is even worse for some scientists in Europe than it is in the USA. In 2008, the European Commissionf ound that women's hourly earnings were an average 17,5 %l ower than men's when all industries were considered. Female scientists are also more likely to be assigned to jobs for whicht here is less recognition.F or example, a2 010 UK survey showed that women spent more hours per week teaching and fewer hours conducting research than male academics, putting them at ad isadvantage for promotion. It is surprising then that women do not complain more about the bias or discrimination they experience. Reasonsc ould be that they are lessa ware of it or do not want to appear to complain because of af ear of jeopardizingt heir career.Another aspecto fw omen dropping out of STEM careers or out of the workforce entirely is the loss of income to the nation's economy. A2 012 report from Credit Suisse points out that companies with women as board members produce better business results than boardsc onsisting of only men, which underlines the positive impact of genderdiversity.Researchf rom the AmericanA ssociation for University Women shows that people still tend to associate the STEM disciplines with men and to hold negative opinions of women in "masculine" careers, with women who are successful in those positions judged to be less likeable. This demonstrates the need for more women in the academic fields of STEM as role modelst oc hange this perception.A ccording to another study, UK womenp ursuing PhDs in STEM undervalued their training and experience and tendedt ob elieve less in their achievements,i deas, and meritst han men.Reasons that hold women back in STEM careers are certainly individual, complex, and manifold;t herefore, it is important to look at factorso utside of academia that are occurring in women's livesa tt he same time that they are pursuing their career search. The mosto utstanding factor that occurs at this crucial time is family formation. As women are continuingt heir academic careers they are also stepping into their new role as aw ife and mother. For women with children it is definitively more difficultt of ollow their career.T hey need as upportive structure that enables them to continue to keep working. As our society relies on having children, it becomes clear that those supportive structures have to come from every side of society,politics,employers, and the families themselves.Anumber of organizationshave been set up to combatstereotyping...

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Treatment of o-alkyl-2-enoxycarbonyl-a-diazoacetophenones with rhodium acetate results in an initial cyclization to give a six-ring carbonyl ylide which undergoes a subsequent intramolecular dipolar cycloaddition with the neighboring double bond.* Dedicated to Howard E. Zimmerman on the occasion of his 60th birthday.