Enantioselective Desymmetrization of cis-3,5- O-Arylidenecyclohexanones Catalyzed by Cinchona-Derived Quaternary Ammonium Salts.

An enantioselective protocol for the desymmetrization of cis-3,5- O-arylidenecyclohexanones has been developed that proceeded under the catalysis of readily available and inexpensive Cinchona-derived quaternary ammonium salts. The synthetic relevance of the methodology was exemplified by the synthesis of a key intermediate that could be used in the preparation of the active pharmaceutical ingredient, paricalcitol (Zemplar).

Pharyngolaryngo-esophagectomy with laparoscopic gastric pull-up: a reappraisal for the pharyngoesophageal junction cancer.

Background: Surgical treatment of advanced hypopharyngeal tumors is still a surgical challenge. We report a case of a hypopharyngeal tumor treated with a pharyngolaryngo-esophagectomy (PLE) and laparoscopic gastric tubulization and interposition.

Methods: A 56-year-old man presented with a relapsing hypopharynx carcinoma, after primary chemoradiation therapy.

Single-access laparoscopic "lavage" for purulent diverticulitis in a 96-year-old patient: how to reduce surgical trauma and standardize surgical technique.

Introduction: Recently, laparoscopic lavage emerged as an effective alternative for patients with perforated diverticulitis with purulent peritonitis.

Case Report: A 96-year-old woman, diagnosed with Hinchey 3 diverticulitis after a computed tomography scan, was operated on with a single-access "lavage" to reduce surgical trauma and to avoid stoma.

Methods: The procedure was performed under general anesthesia.

Image-guided robotic radiosurgery (CyberKnife) for pancreatic insulinoma: is laparoscopy becoming old?

Insulinomas constitute about 25% of endocrine pancreatic tumors. Laparoscopic surgery is the treatment of choice. However, pancreas-related complications rate is very high, even in experienced hands, ranging up to 37%.

Standard laparoscopic versus single-incision laparoscopic colectomy for cancer: early results of a randomized prospective study.

Background: Standard laparoscopic colectomy (SLC) for cancer is a safe, feasible, and oncologically effective procedure with better short-term and similar long-term results of open colectomy. Conversely, owing to technical difficulties in colonic resection and full mesenteric dissection, single-incision laparoscopic colectomy (SILC) has been considered unsuitable for oncologic purposes. We compared the technical feasibility and early clinical outcomes of SLC and SILC for cancer.

Laparoscopic left nephrectomy with "en bloc" distal splenopancreatectomy.

Background: Multiorgan resection for cancer is considered a demanding laparoscopic procedure. We report a laparoscopic radical nephrectomy and distal splenopancreatectomy for a locally advanced kidney tumor.

Methods: A 67-year-old woman presented with left flank pain and hematuria.

Unexpected side reactions of imidazolium-based ionic liquids in the base-catalysed Baylis-Hillman reaction.

Low yields are obtained when the Baylis-Hillman reaction is conducted in the presence of an imidazolium-based ionic liquid due to direct addition of the deprotonated imidazolium salt to the aldehyde. Ionic liquids are evidently not inert.

Rate acceleration of the Baylis-Hillman reaction in polar solvents (water and formamide). Dominant role of hydrogen bonding, not hydrophobic effects, is implicated.

A substantial acceleration of the Baylis-Hillman reaction between cyclohexenone and benzaldehyde has been observed when the reaction is conducted in water. Several different amine catalysts were tested, and as with reactions conducted in the absence of solvent, 3-hydroxyquinuclidine was found to be the optimum catalyst in terms of rate. The reaction has been extended to other aldehyde electrophiles including pivaldehyde.

Metal- and Ligand-Accelerated Catalysis of the Baylis-Hillman Reaction.

The Baylis-Hillman reaction, the coupling of an unsaturated carbonyl compound/nitrile with aldehydes, is a valuable reaction but is limited in its practicality by poor reaction rates. We have endeavored to accelerate the reaction using Lewis acids and found that while conventional Lewis acids gave reduced rates group III, and lanthanide triflates (5 mol %) gave increased rates. The optimum metal salts were La(OTf)(3) and Sm(OTf)(3), which gave rate accelerations (k(rel)) of approximately 4.